掲載種別：研究論文（学術雑誌）   出版者・発行元：Elsevier BV  

DOI： 10.1016/j.revmic.2020.100423

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：PALAEONTOLOGICAL SOC JAPAN  

Turbocapsula, having three (or four) segments with a characteristic oval shape and a hemi-closed segmental end, is a radiolarian genus with a high stratigraphic value due to its phyletic evolution in the mid-Cretaceous period. An overview of lithology, depositional setting, associated fossil records, and paleomagnetic data from each locality of Turbocapsula costata (Wu) is summarized. All these data lead to the conclusion that locations of known T. costata-bearing strata are restricted to the low- to mid-latitude Mediterranean and eastern Tethys of the Tethyan realm. The results emphasize that the phyletic evolution of the genus Turbocapsula is significant in correlations within the Tethys. The zonation established by the phyletic evolution of the genus Turbocapsula cannot be utilized for Early Cretaceous zonal correlations beyond the T. costata territory.

DOI： 10.2517/2019PR015

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：PALAEONTOLOGICAL SOC JAPAN  

The three-dimensional morphology of the flat-shaped spumellarian radiolarian Dictyocoryne was analysed using a microfocus X-ray CT with a special focus on whether it was capable of a planktonic lifestyle. Two types of 3D models, the shell model, which represents a realistic 3D shell, and the wrapped model, which mimics the whole body outline without pseudopodia, were reconstructed in order to estimate volume, surface area, and centres of gravity for the shell model and buoyancy for the wrapped model. The calculated values showed that the volume of shell with respect to the total volume was negatively allometric, regardless of the differences between threshold settings. Stepwise secretions of the patagium layer may result in a comparatively lightweight shell, thereby decreasing the total density during growth but not below the density of seawater. Estimated positions for the centres of gravity and buoyancy were too close to maintain an autonomous posture while floating. Instead, the ratio between surface area and volume was greater than that in an ideal sphere. Such a broad surface area could obtain the viscous resistance necessary for sinking retardation. Spumellarian radiolarians, including Dictyocoryne, have photosynthetic symbionts located primarily in the ectoplasmic layer, which is a habitable space that can be maximised within the larger surface area. Given that radiolarians float when extending their pseudopodia, it can be hypothesised that pseudopodia may play a role in the adjustment of life posture in a hydraulically unstable shell, which can be integrated into sinking retardation, enhancement of photosynthetic activity and manoeuvrability of life posture within a unique flat-shaped morphogenesis.

DOI： 10.2517/2019PR020

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記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）  

添付ファイル： Sakai_et_al_2020.pdf

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD  

Early Cretaceous plants are widely distributed in a number of localities and horizons in the Tetori Group in central Japan. However, the stratigraphical occurrences and diversity patterns of some plant groups and their palaeoclimatic implications are not well understood. In this study, we report the diverse fossil plants recently collected from the Lower Cretaceous Itsuki and Nochino formations of the Tetori Group in the Kuzuryu area, central Japan. The plant assemblage from the lower and middle part of the Itsuki Formation has no Ryoseki-type floral element, whereas the assemblage from the Nochino Formation has some Ryoseki-type floral elements such as microphyllous conifers. The occurrence of Ryoseki-type floral elements is consistent with floral change that conifers are more diverse in the Nochino Formation than in the Itsuki Formation, and a warming and drying climate trend from the Itsuki Formation to the Nochino Formation is recognized. The Early Cretaceous warming and drying trend recorded in floral assemblages of the Tetori Group is considered to reflect the paleoclimate transition represented by drastic shrinking of the Hadley circulation in the mid-latitudes of East Asia, thus providing evidence for understanding the climatic switch pattern during the Early Cretaceous. (C) 2019 Published by Elsevier Ltd.

DOI： 10.1016/j.cretres.2019.01.018

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.5566/ias.2089

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：PALAEONTOLOGICAL SOC JAPAN  

The Nadanhada terrane of northeastern Heilongjiang, northeastern China is composed of Jurassic accretionary complexes (i.e., the Yuejinshan Complex in the west, the Raohe Complex in the east) and succedent cover beds. In this paper we report two radiolarian assemblages recognized from four black clay stone samples collected from the Dalinggiao Formation in the Dajiashan area of the Raohe Complex. The Striatgjaponocapsa synconexa-"Tricolocapsa" tetragona assemblage of one sample consists of eleven species in eight genera, which indicates a middle Bathonian (Middle Jurassic) age, i.e., correlative with the uppermost Striatojaponocapsa plicarum Zone to the lower Striatojaponocapsa conexa Zone. The other three samples contain 34 species in 25 genera, which indicate a late Oxfordian-early Tithonian (Late Jurassic) age. The discovery of the Late Jurassic radiolarian assemblage indicates that the Raohe Accretionary Complex was formed during the Late Jurassic. The succedent late Tithonian-early Valanginian Buchia fauna-bearing Dong'anzhen Formation may be the earliest cover beds overlying the Raohe Accretionary Complex. Then, during the Early Cretaceous, the Nadanhada terrane received the deposition of the Aucellina bivalve fauna-bearing Dajiashan Group. This indicates paleogeographic differentiation between the Nadanhada terrane and the Tamba-Mino-Ashio terrane.

DOI： 10.2517/2019PR006

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：PALAEONTOLOGICAL SOC JAPAN  

The Guadalupian (Permian) Gufeng Formation, distributed over the north margin of the South China block, is characterized by siliceous rock and muddy rock and yields several representative radiolarian fossils. The lithostratigraphy, radiolarian occurrences and biostratigraphy, and geochemical characteristics of the Gufeng Formation are reviewed and summarized in this paper. The distributional area of the Gufeng Formation is subdivided into the Lower, Middle, and Upper Yangtze regions. The Gufeng Formation in the Lower Yangtze region is lithostratigraphically characterized by muddy rock, chert, and nodule-bearing muddy rock in descending order. The Gufeng Formation in the Middle Yangtze region is lithostratigraphically characterized by chert, muddy rock with carbonate, and muddy rock in ascending order. The lithostratigraphic characteristics of the "Gufeng Formation" in the south margin of the South China block greatly differ from the typical Gufeng Formation in containing fewer siliceous rocks and a large amount of elastic rocks and in having a significantly greater total thickness; therefore, this article considers that the "Gufeng Formation" in the block's south margin should be isolated from the Gufeng Formation in the block's north margin. The radiolarian biostratigraphy of the Lower and Middle Yangtze regions is composed of the Pseudoalbailella globosa, Pc. monacantha, and Follicucullus scholasticus-Ruzhencevispongus uralicus assemblage zones in ascending order. The lower Gufeng Formation has abundantly yielded the Albaillellaria; however, its occurrence ratio with respect to other radiolarian orders decreases stratigraphically upward. The geochemical characteristics indicate the following facts: (1) the siliceous rocks are generally biogenic; (2) even though a previous study concluded that the organic matter within the chert was originated from terrestrial or reworked organic matter, the origin remains debatable; and (3) the Gufeng Formation was formed on a continental shelf. The geochemical characteristics, in addition to the lithological characteristics, indicate that the redox conditions of the Gufeng Formation in the Lower Yangtze region changed from aerobic to suboxic to anoxic, while that in the Middle Yangtze region changed from oxic to anoxic to suboxic.

DOI： 10.2517/2018PR025

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WILEY  

Abundant Triassic radiolarian fossils were obtained from varicolored bedded cherts exposed in the Buruocang section near Jinlu village, Zedong, southern Tibet. The radiolarian-bearing rocks represent fragmented remnants of the Neotethys oceanic sediments belonging to the melange complex of the east part of the Yarlung-Tsangpo Suture Zone. Two new middle Late Anisian radiolarian assemblages recognized from this section named Oertlispongus inaequispinosus and Triassocampe deweveri, respectively, are compared with those known from Europe, Far East Russia, Japan, and Turkey. These Anisian radiolarian fossils are the first reported in southern Tibet and the oldest radiolarian record within the Yarlung-Tsangpo Suture Zone. They improve time constraints for the evolution of Neotethys in southern Tibet.

DOI： 10.1111/iar.12302

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掲載種別：研究論文（学術雑誌）  

© 2018 The Author(s) Pelagic cherts preserved in accretionary complexes represent former seafloor sediment that can retain geochemical evidence of paleoceanographic conditions that predate the oldest extant oceanic crust. The ratio of Os isotopes in seawater, in particular, is of wide interest as a source of insight into notable geologic events such as oceanic anoxic events, rapid global warming episodes, and eruption of large igneous provinces, but marine Os isotope records from before 80 Ma are scarce. We present a record of secular variations of marine Os isotope ratios from a thick, continuous succession of Middle and Upper Triassic pelagic chert in the Sakahogi section of the Mino Belt accretionary complex. Initial Os isotope ratios (187Os/188Os) have a wide range in this succession, from 0.197 to 0.813. The variations in this Os record are quite similar to those in the marine Sr isotope record for the same time period, although their amplitudes differ owing to the differing residence times of Os and Sr in the ocean. Together, our results and previous data trace a continuous Os isotope record for ca. 50 Myr starting in Anisian time. We document the following six notable features in the Os record, which also appear in the Sr record, and their interpretation: (1) a negative (unradiogenic) shift associated with euxinia in the latest Anisian reflecting late-stage Siberian Traps eruptions, (2) wide fluctuations from the latest Anisian to Ladinian induced by volcanism and by the late Ladinian humid pulse and volcanism of the Italian Volcanic Center, (3) a continuous decrease in the early Carnian during eruptions of the Wrangellia large igneous province, (4) stable unradiogenic values from the early to early middle Norian associated with a prolonged arid period, (5) a negative spike in the middle Norian associated with the Manicouagan impact event, and (6) a broad rise and fall from the earliest late Norian to the Rhaetian ages, attributed to the Cimmerian-Indosinian orogeny and subsequent volcanism of the Central Atlantic Magmatic Province.

DOI： 10.1016/j.jaesx.2018.100004

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担当区分：筆頭著者  

添付ファイル： 243_Matsuoka_Ito_2019_SRNU.pdf

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WILEY  

The Yarlung-Tsangpo Suture Zone (YTSZ), as the southernmost and youngest among the sutures that subdivides the Tibetan Plateau into several east-west trending blocks, marks where the Neo-Tethys was consumed as the Indian continent moved northward and collided against the Eurasian continent. Melanges in the YTSZ represent the remnants of the oceanic plate through subduction and collision. Melanges are characterized by a highly sheared volcanoclastic or siliceous mudstone matrix including blocks of chert, claystone, and basalt. Detailed radiolarian analyses are conducted on the melange near Zhongba County. Macroscopic, mesoscopic, and microscopic observations are combined in order to elucidate the relationships among age, lithology, and structure of blocks in the melange. Reconstructed ocean plate stratigraphy includes Lower Jurassic limestone within the chert sequence accumulated at a depth near the CCD (Unit 2), Upper Jurassic thin-bedded chert interbedded with claystone deposited in the wide ocean basin (Unit 3), and Lower Cretaceous chert with siliceous mudstone (Units 4 and 5), representing the middle parts of ocean plate stratigraphy. The results highlight the fabric of brecciated chert on mesoscopic scale, which is thought to be due to localized overpressure. The formation of mesoscopic and microscopic block-in-matrix fabrics in the melange is proposed for the chert and siliceous mudstone bearing different extents of consolidation and competence during the progressive deformation of accreted sediments at shallow-level subduction.

DOI： 10.1111/iar.12282

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：一般社団法人 日本地質学会  

<p>The Tetori Group in the Shiramine area (Ishikawa Prefecture, central Japan) is subdivided into the Gomijima, Kuwajima, Akaiwa, and Kitadani formations (from bottom to top). A variety of animal and plant fossils have been reported from the Kuwajima, Akaiwa, and Kitadani formations, but the depositional ages are still poorly constrained. We obtained the first reliable zircon U-Pb age from the Akaiwa Formation of the Tetori Group in the Shiramine area using laser ablation inductively coupled plasma mass spectrometry. The dated sample was taken from the lower part of the Akaiwa Formation along the Osugidani River (Shiramine area), and its U-Pb age is 121.2±1.1 Ma (95% confidence interval).</p>

DOI： 10.5575/geosoc.2018.0062

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担当区分：筆頭著者   掲載種別：研究論文（学術雑誌）   出版者・発行元：Scientific Research Publishing, Inc.  

DOI： 10.4236/ojg.2019.910039

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記述言語：英語   出版者・発行元：ELSEVIER FRANCE-EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER  

Mesozoic radiolarian biochronologic scales have been developed since the 1970s and most of them reached their present day status in the1990s. The degree of temporal resolution, on average, corresponds to substage level and is sufficient to provide a meaningful framework for general geological studies. The great majority of zonal schemes were elaborated in low-latitude sections but are applicable in high latitudes as well because an adequate number of species occur worldwide. This paper presents a short historical review and a synthesis of currently used zonations developed in North America, Europe and Asia. The advantages and the shortcomings of the existing zonations are discussed. As a general rule, the zonations including a high number of taxa in each zone have a much greater applicability for global correlations than those defined exclusively with marker taxa. In the forthcoming years, particular studies will focus on zonal division of under-explored time intervals and on improved calibration to chronostratigraphy. Two joint objectives for future research are briefly introduced. The first objective, achievable in a relatively short time, is to compile a composite Mesozoic zonation that would provide a single reference standard for radiolarian dating at a global scale. The second objective is to refine the radiolarian zonal schemes, which, in certain intervals, have already attained the resolution comparable to that of the standard ammonite zones. To increase the degree of precision and accuracy to this level through the entire Mesozoic is a long-term goal that requires additional high-resolution sampling and emphasis on detailed documentation of evolutionary first and last appearances in different phylogenetic lineages. (C) 2018 Elsevier Masson SAS. All rights reserved.

DOI： 10.1016/j.revmic.2018.08.001

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1111/iar.12271

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1111/iar.12273

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.5575/geosoc.2017.0074

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Palaeontological Society of Japan  

An upper Paleocene radiolarian-bearing succession (ZN1) located in the southern part of the north subzone of the Tethyan Himalaya is composed of siliceous siltstones and claystones. In this paper, 23 species belonging to 13 genera are reported. Three new species, Lychnocanium? pyramis Li and Matsuoka sp. nov., Lychnocanium? stypticum Li and Matsuoka sp. nov., and Pterocyrtidium sinense Li and Matsuoka sp. nov., are described. Radiolarian assemblages from this succession can be compared with the Bekoma campechensis Zone (RP6), indicating a time interval of 61.5-58.23 Ma, i.e., late Paleocene. The radiolarian assemblages from the Yamdrok mélange, the Zheba section, and the Jiazhu section indicate that they are of the same age as those from the Zhinadibu 1 section. The lack of calcareous and coarse-grained terrestrial materials in the ZN1 section proves that the strata of this section were deposited in a relatively deep marine environment below the calcium carbonate compensation depth (CCD) and more distal to the continents during the late Paleocene. Coeval deepwater sediments near Saga were accumulated near the CCD.

DOI： 10.2517/2017PR009

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

Guiuva sashidai Ito and Feng n. gen. n. sp., characterized by bunchy aggregations comprising combined small spherical shells with porous surfaces, was discovered from the Lopingian (Upper Permian) of the Yutouling section in the Xiaodong area, Guangxi Zhuang Autonomous Region, South China. The morphological similarities with recent radiolarians and formation of the aggregations imply that this species is a colonial radiolaria. This species is ca. 200 myr older than previously-reported occurrences of colonial radiolarians from the Eocene. It is believed that colonial radiolarians live exclusively in association with symbiotic algae, based on previous observations of the extant forms. Therefore, it is plausible to suggest that G. sashidai had symbionts, which would indicate that the origin of symbiont-bearing radiolarians dates back at least to the Permian. On this basis, we suggest that this is the oldest known example of symbiont-bearing radiolarians. (C) 2017 Elsevier Ireland Ltd Elsevier B.V. and Nanjing Institute of Geology and Palaeontology, CAS. Published by Elsevier B.V. All rights reserved.

DOI： 10.1016/j.palwor.2017.04.001

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記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：新潟大学理学部  

InterRed XV in Niigata 2017 Niigata University (JAPAN) Oct/22-Oct/27, 2017Ie Island in northwestern Okinawa Prefecture, Japan, mainly comprises of basement rocks (Gusukuyama Formation of the Southern Chichibu terrane) and the overlying Pleistocene Ryukyu Group. The bedded cherts of the Gusukuyama Formation in Mt. Gusuku in the central part of Ie Island have yielded radiolarians ranging from the Neoalbaillella optima Zone (Changhsingian, Lopingian, Permian) to the Kilinora spiralis Zone (JR6: Oxfordian, Upper Jurassic). Siliceous mudstones in the southern flank of Mt. Gusuku have yielded radiolarians of the Pseudodictyomitra carpatica Zone (KR1: uppermost Jurassic–lowermost Cretaceous). This age difference is assumed to indicate the presence of a thrust between Mt. Gusuku and the southern flank of the mountain. Red chert clasts are contained in the Pleistocene Ryukyu Group at Waji on the north coast of Ie Island, and Permian radiolarians have been obtained from chert clasts. In addition, a red bedded chert boulder at Waji yielded Cisuralian (Early Permian) radiolarians including dimorphic pair of Albaillella sinuata Ishiga and Watase.

添付ファイル： 226_Ito_Matsuoka_2017_SRNU.pdf

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記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：新潟大学理学部  

InterRed XV in Niigata 2017 Niigata University (JAPAN) Oct/22-Oct/27, 2017The Okinawa Radiolarian Tour, an annual workshop on living radiolarians, has been held at the Sesoko Station, the Tropical Biosphere Research Center of the University of the Ryukyus in Okinawa Prefecture, Japan, since 1997. More than 200 researchers and students have joined this tour to observe living radiolarians. The tours have provided valuable knowledge on living radiolarians, such as faunal characteristics, biological activities, skeletal growth, and molecular phylogeny. In this guide, brief histories of radiolarian biological research and the Okinawa Radiolarian Tour are given. Practical, latest information on oceanographic conditions, travel, safety, and handling and storage procedures for radiolarian studies will be given at the Sesoko Station.

添付ファイル： 225_Matsuoka_et_al_2017_SRNU.pdf

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記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：新潟大学理学部  

InterRed XV in Niigata 2017 Niigata University (JAPAN) Oct/22-Oct/27, 2017The Itoigawa UNESCO Global Geopark is located in Itoigawa City, Niigata Prefecture in central Japan. This geopark was approved as a Global Geopark in 2009, which is one of the first Global Geoparks in Japan. The Itoigawa–Shizuoka Tectonic Line, which divides the Japanese Islands into Southwest Japan and Northeast Japan in the Cenozoic tectonic framework, lies in the central part of the City of Itoigawa. Various rocks, ranging in age from the Cambrian to Quaternary, and cultural legacies can be observed in the 24 geosites in this geopark. Silurian, Permian, Triassic, and Jurassic radiolarians have been discovered from Itoigawa.

添付ファイル： 224_Ito_et_al_2017_SRNU.pdf

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：GEOLOGICAL SOC PUBL HOUSE  

An aberrant bi-apical Follicucullus specimen (Albaillellaria, Radiolaria) has been discovered from an upper Guadalupian (Middle Permian) chert block of the Kamiaso Unit of the Mino terrane, central Japan. If this specimen was formed with double malformation, it would be the oldest record of this phenomenon in radiolarians and the first record of its kind in Albaillellaria.

DOI： 10.1144/jmpaleo2016-016

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

We recovered a Campanian-Maastrichtian palynological record in transitional succession from the Sifangtai to Mingshui formations of the Songke Core-1 (North) (SK1 (N)) in the Songliao Basin, Northeast China. These formations are composed mainly of various colored mudstones and sandstones. The lithofacies variation suggests that the paleoenvironment changed from flood plain to lake. Most of the palynomorph assemblages are dominated by gymnosperm pollen, followed by spore of pteridophyte, and angiosperm pollen. On the basis of the first occurrences of marker genera within the succession, we identified four palynomorph interval zones (in ascending order): the Jianghanpollis, Chenopodipollis, Toroisporis, and Betulaceoipollenites interval zones. The first two interval zones are found from flood plain and levee deposits. The third one is recognized from lake basin plain-lake basin slope deposits. The last one is found in delta deposits within lakeshore. We consider that environmental changes are the major factors that formed component of Campanian-Maastrichtian assemblage in the Songliao Basin. In addition, the Jianghanpollis and Chenopodipollis interval zones are assigned to the Campanian, whereas the Toroisporis and Betulaceoipollenites interval zones date as the Maastrichtian. Thus, the Chenopodipollis/Toroisporis zonal boundary approximates the C/M boundary. Triprojectate pollen such as Aquilapollenitesis regarded as marker taxa in the study section and other areas within the Aquilapollenites Province during the Campanian-Maastrichtian. However, Wodehouseia spp. have yet been confirmed within the study section, although this genus has appeared in Campanian-Maastrichtian deposits in other areas. This is one of the important clues to understand regional difference of local flora in these ages. (C) 2016 Elsevier B.V. and Nanjing Institute of Geology and Palaeontology, CAS. All rights reserved.

DOI： 10.1016/j.palwor.2016.10.001

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記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：新潟大学理学部  

This catalogue contains 14 spumellarian and 15 nassellarian species commonly occurring in surface waters in the East China Sea around Sesoko Island, Okinawa Prefecture, Japan. Each panel consists of live and skeleton images with transmitted light microscopy and skeleton images with scanning electron microscopy of each species. The fauna is composed of shallow dwellers in subtropical waters.

添付ファイル： 221_Matsuoka_2017_SRNU.pdf

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記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：新潟大学理学部  

Morphological re-examination under a scanning electron microscope (SEM) of the type specimens of Diestheria longinqua Chen, in Zhang et al., 1976 from the Lower Cretaceous Yixian Formation of the Jehol Group at Dakangpu of Yixian County, western Liaoning Province, northeastern China revealed morphological features on the carapace that had not been recognized previously: 1) growth lines with fine ridges; 2) radial lirae intercalated with small irregular reticulation on the growth bands in the postero-middle part of the carapace.

添付ファイル： 220_LiYuling_et_al_2017_SRNU.pdf

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記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：新潟大学理学部  

This article describes radiolarians from a radiolarite pebble within conglomerate from a float block that was collected along the banks of the Kotaki River in the Kotaki area, Itoigawa, Niigata Prefecture, central Japan. Futobari morishitai Furutani, Inaniguttidae gen. et sp. indet., and Palaeoscenidiidae gen. et sp. indet. were recognized on etched surfaces of the pebble. Pseudospongoprunum sp., Zadrappolus sp., and Rotasphaera sp. were discovered in residues obtained by chemically treating the conglomerate. This assemblage may be compared to the assemblage around the boundary between the Pseudospongoprunum tauversi to Futobari solidus-Zadrappolus tenuis assemblage zones and corresponds to the late Silurian. This report marks the first identification of Silurian radiolarians in Niigata Prefecture, which also makes them the oldest recorded fossils from the prefecture. The clasts are also the oldest recorded radiolarian-bearing clasts within conglomerates of the Japanese Islands and the Korean Peninsula.

添付ファイル： 219_Ito_et_al_2017_SRNU.pdf

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

A radiolarian biostratigraphic study ranging from the latest Barremian to the Aptian of a pelagic sequence (section BB1) near Babazhadong in southern Tibet revealed phyletic relationships of species belonging to the genus Turbocapsula. Three species and two subspecies are included in this genus: Turbocapsula tetras LI & MATSUOKA, n. sp., T. fugitiva O'DOGHERTY, and T. costata (T. costata (WU) multicostata LI & MATSUOKA, n. ssp. and T. costata (WU) costata). Turbocapsula fugitive appears to have arisen from T. tetras by losing the septa between the third and the fourth segments. Turbocapsula fugitiva seems to have given rise to T. costata multicostata following the development of thicker costae between its two to five rows of pores. With the decrease in the number of the costae and the development in the costae, T. costata multicostata evolved into T. costata costata. The phyletic evolution of the genus Turbocapsula has a high stratigraphic value. Based on the phyletic evolution of Aurisaturnalis and Turbocapsula, two radiolarian zones have been defined: the Aurisaturnalis carinatus Zone and the Turbocapsula costata Zone. These zones are defined by evolutionary first appearance bio-horizons (EFABs), which are more reliable than the first and the last occurrence bio-horizons over wide areas. The Turbocapsula costata Zone is subdivided into the Turbocapsula costata multicostata Subzone and the Turbocapsula costata costata Subzone. Based on comparisons with radiolarian biostratigraphic research conducted in other areas, in which age-diagnostic calcareous nannofossils and planktonic foraminifera occur alongside radiolarians, the Aurisaturnalis carinatus Zone and the Turbocapsula costata Zone are assigned to the Lower Hauterivian-Lower Aptian and the Lower Aptian-Lower Albian, respectively. This newly proposed zonation is useful for comparing the stratigraphic relationships of Turbocapsula-bearing horizons in other areas. A zonal scheme like this scheme can be used for identifying certain episodes such as mid-Cretaceous oceanic anoxic events (OAEs) in the pelagic realms. The Early Aptian OAE la is located between the first appearance bio-horizon of the genus Turbocapsula and the EFAB of T. costata multicostata. (C) 2016 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.marmicro.2016.11.002

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

添付ファイル： 230_Ibaraki_et_al_2017_J.pdf

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

添付ファイル： 229_Ito_et_al_2017_J.pdf

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：OFIOLITI  

Late Mesozoic neritic-continental strata of East Asia show intercalations of conglomerates including microfossil-bearing clasts. Some clasts are presumed to have originated in mid-Mesozoic accretionary complexes (ACs) of East Asia. Microfossils (e.g., radiolaria, conodonts) in these clasts can provide age constraints. Relationships between rock facies and age in sequences of the mid-Mesozoic ACs have been clarified in previous studies; therefore, the rock facies and the age of the clasts offer a clue about denudation history and provenance of the mid-Mesozoic ACs. This study compiles previous studies of microfossil-bearing clasts within the Late Mesozoic in the Outer and Inner zones of Southwest Japan and in the Gyeongsang Supergroup in the southeastern Korean Peninsula.
The compilation, at present, recognizes three denudation stages (Stages A, B, and C) of the mid-Mesozoic ACs. Stage A (Oxfordian-Hauterivian) is characterized by an initial and narrow denudation. The denudation of the mid-Mesozoic ACs started at some point in this stage, but it was of limited extent. Stage B (Barremian-early Albian) is characterized by wide denudation: the mid-Mesozoic ACs became largely exposed. Afterwards, some younger geologic bodies of the mid-Mesozoic ACs, which were structurally underlying, were exposed and denuded. Stage C (late Albian-) is characterized by denudation of almost all the mid-Mesozoic ACs. This denudational evolution might be related to some tectonic and igneous events in East Asia, such as the uplift of the Tetori Group in the late Hauterivian-early Barremian and the initiation of the granitic magmatic activity in the middle Albian.

DOI： 10.4454/ofioliti.v42i2.447

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WILEY  

The Permian planktonic distribution is not well known, in contrast to other fossil distributions of nekton and benthos. Radiolaria are representative microfossils of plankton in the Permian palaeocean. This study compares both correlated radiolarian occurrences (Pseudotormentus De Wever et Caridroit and Quadriremis Nazarov et Ormiston) in literature data from the Pacific Rim and quantitative data from the Liuhuang and Gujingling sections in South China. Pseudotormentus distributions are concentrated in the Panthalassa, whereas Quadriremis occurrences are distributed over both the Panthalassa and the Palaeotethys. The uneven distribution of Pseudotormentus seems to have been controlled by a difference in the oceanic basins, indicating the presence of faunal differences in Permian planktonic microorganisms between the Panthalassa and the Palaeotethys. In other words, this study infers the provincialism of Permian planktonic microorganisms. The uneven distribution is explainable by a hypothesis that Pseudotormentus was strongly affected by a Panthalassan equatorial current.

DOI： 10.1111/1755-6724.12804

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：NATURE PUBLISHING GROUP  

Extinctions within major pelagic groups (e.g., radiolarians and conodonts) occurred in a stepwise fashion during the last 15 Myr of the Triassic. Although a marked decline in the diversity of pelagic faunas began at the end of the middle Norian, the cause of the middle Norian extinction is uncertain. Here we show a possible link between the end-middle Norian radiolarian extinction and a bolide impact. Two palaeoenvironmental events occurred during the initial phase of the radiolarian extinction interval: (1) a post-impact shutdown of primary and biogenic silica production within a time span of 104-105 yr, and (2) a sustained reduction in the sinking flux of radiolarian silica for similar to 0.3 Myr after the impact. The catastrophic collapse of the pelagic ecosystem at this time was probably the dominant factor responsible for the end-middle Norian conodont extinction.

DOI： 10.1038/srep29609

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD  

The heteromorph ammonite Pravitoceras sigmoidale Yabe, of the family Nostoceratidae, is the zonal marker of the upper Campanian P. sigmoidale Zone in southwest Japan, and is the main component of ammonite assemblages in this zone. We explain the taphonomic processes underlying the occurrence of P. sigmoidale in the Izumi Group, specifically in the Minato (Awaji Island), Anaga (Awaji Island), Koike -Omoizaki (Shikoku), and Hidonodani sections (Shikoku). The first two sections consist mainly of the non-turbiditic Northern Marginal Facies (NMF), while the latter two sections comprise the Main Fades (MF), a turbiditic facies deposited in waters deeper than those of the NMF. We recognise three modes of occurrence of P. sigmoidale, as follows: (1) In nodules crowded with P. sigmoidale (NCP); this mode occurs only in the NMF, and includes juvenile and adult specimens, together with other ammonites such as Solenoceras (Oxybeloceras) aff. humei (Douville), (2) In mudstone with isolated P. sigmoidale (MIP), which is found in all of the sections studied, (3) In sandstone with isolated P. sigmoidale (SIP), which occurs only in the MF. Adult individuals of P. sigmoidale are dominant in most of the sections, while juveniles were observed only in the Minato section, which originally was closer to land areas. The number of specimens of P. sigmoidale and Solenoceras spp. tends to increase in sections representing depositional environments proximal to terrestrial areas. Ammonite assemblages could have been transported from shallow- to deep-water settings by turbidity currents. The sorting of components by transport processes likely contributed to the formation of these fossil assemblages in different areas. This is an important clue to understanding the habitat of heteromorph ammonite life assemblages consisting mainly of P. sigmoidale. (C) 2016 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.cretres.2016.02.003

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.5575/geosoc.2016.0013

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記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：新潟大学理学部  

Morphological re-examination of the specimen of Ganestheria longnanensis Bi and Xie from the Upper Cretaceous Zhoutian Formation in Chenglong Village, Longnan County, Jiangxi Province, southeastern China under a scanning electron microscope SEM) revealed morphological features on the carapace that had not been recognized previously: widely spaced radial lirae on growth bands intercalate large-sized polygonal reticulation, within which small-sized reticulation also occurs

添付ファイル： 207_LiGang_et_al_2016_SRNU.pdf

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記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：新潟大学理学部  

A new species, Nestoria sikeshuensis Teng and Li sp. nov., is described from the core of the bore hole Ai2 in the Junggar Basin, northwestern China. These specimens were collected from the Lower Cretaceous Tugulu Group. In Xinjiang, only three species and two undeterminated species of Nestoria have been reported in the literature before.

添付ファイル： 208_TengXiao_et_al_2016_SRNU.pdf

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.5047/forma.2016.002

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

添付ファイル： 215_Ito_et_al_2016_NOM_L.pdf

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

添付ファイル： 213_LiX_Matsuoka_2016_NOM_L.pdf

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

添付ファイル： 214_Ito_Matsuoka_2016_NOM_L.pdf

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記述言語：日本語   出版者・発行元：一般社団法人 日本地質学会  

DOI： 10.14863/geosocabst.2016.0_276

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：The Palaeontological Society of Japan  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

添付ファイル： 204_Ito_Matsuoka_2015_NOM15.pdf

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

添付ファイル： 202_Yoshino_et_al_2015_NOM_J.pdf

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

添付ファイル： 203_Yoshino_K_Matsuoka_2015_NOM_J.pdf

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SPRINGER  

The Yoshii Group of the Akiyoshi terrane is distributed over the Otakeyama area, Okayama Prefecture, southwest Japan. The Yoshii Group is composed of siliceous rocks and clastics, comprising chert-clastic sequences. The Yoshii Group is divided into four structural units (Units Ot 1, Ot 2, Ot 3, and Ot 4) in structurally ascending order. Lithological similarities and radiolarian age suggest that these units exhibit almost identical ocean plate stratigraphy. These units are structurally-repeated to form an imbricate structure. This structure was possibly formed by off-scrape accretion at a toe of an accretionary complex. Additionally, a review of previous studies indicates that an imbricate structure is common in the Akiyoshi terrane. The presence of an imbricate structure in the Akiyoshi terrane, Permian accretionary complex, indicates the possibility that a specific horizon of Permian pelagic sequences acted as a d,collement zone.

DOI： 10.1007/s11707-014-0443-x

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：The Geological Society of Japan  

中国東北部では，ジュラ系および白亜系は，主として非海成の地層からなる．中国東北部における非海成層中のジュラ系・白亜系境界の認定は，遼寧省西部から産出するJehol生物群の年代決定に大きく依存している．同生物群の年代観は，幾多の変遷をたどっている．中国，モンゴルおよびロシア・トランスバイカルの含<i>Eosestheria</i>-<i>Ephemeropsis</i>-<i>Lycoptera</i>層は，1920年代には白亜紀古世に位置づけられていた．しかし，1960年代以降は，ジュラ紀中世ないし新世へと変更された．1990年代前半以降，黒竜江省東部から産する海生生物相の年代位置づけが修正されたことにより，Jehol生物群の年代は，再び白亜紀古世を示すと考えられるようになった．最近の放射年代の測定によれば，ジュラ紀・白亜紀境界は，Jehol層群の層準よりもずっと下位に位置づけられる．

DOI： 10.5575/geosoc.2015.0001

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その他リンク： https://jlc.jst.go.jp/DN/JLC/20009209648?from=CiNii

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：The Geological Society of Japan  

A Topic Session entitled "The Jurassic +" has been held during the annual meeting of the Geological Society of Japan since 2003. This paper summarizes the achievements of the topic session over the past ten years, listing the presentation titles and authors. This session has provided a regular opportunity for Jurassic researchers in Japan to exchange data and ideas. It has also contributed to providing the international Jurassic research community with information on the topic sessions through the Newsletters of the International Subcommission on Jurassic Stratigraphy (ISJS). This paper provides an introduction to the recent activities of the subcommission.

DOI： 10.5575/geosoc.2015.0005

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その他リンク： https://jlc.jst.go.jp/DN/JLC/20010528899?from=CiNii

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Elsevier Masson SAS  

We considered the geometrical properties of skeletons of the genus Pantanellium, a type of Mesozoic radiolarian. We constructed four 3D models of fossil specimens of Pantanellium, using X-ray Micro-CT and layered manufacturing technology. Focusing on cortical shells, we approximated the skeletal structures with convex polyhedrons and investigated their geometrical properties. We summarized these properties using planar graphs. The geometrical properties differ for fossils that are believed to belong to the same species. The results of numerical simulations based on a mathematical model for spherical radiolarians were partially consistent with the skeletal structures of the specimens. We conclude that the skeletal structure of the genus Pantanellium is not fixed and is not completely optimized from the viewpoint of symmetry.

DOI： 10.1016/j.revmic.2015.01.002

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Elsevier Masson SAS  

Middle Permian Pseudoalbaillella from the Xiaodong area in South China were studied using fossil morphology. Short forms of Pseudoalbaillella fusiformis (Holdsworth and Jones), Pseudoalbaillella internata Wang, and Pseudoalbaillella monacantha (Ishiga and Imoto), characterized by a short and skirt-like pseudoabdomen, were confirmed. We conclude that the short forms were derived from their respective species by breaking off during disruptive processes. If this is true, there may be structurally weakened parts in the pseudoabdomen.

DOI： 10.1016/j.revmic.2014.05.003

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：新潟大学理学部  

Morphological reexamination of the type specimems of Eosestheria sihetunensis from the Jianshangou beds, the lowest fossil bearing part of the Lower Cretaceous Yixian Formation in Sihetun Village of Beipiao City, western Liaoning Province, northeastern China under a scanning electron microscope (SEM) revealed morphological features on the carapace that had not been recognized previously: growth lines with fine ridges; growth bands near the umbo and in the middle part of the carapace are ornamented with reticulation, within which very fine ridges or cross bars and punta are observed; growth bands in the ventral part of the carapace ornamented with radial lirae, which expand to form triangularly enlarged structure.

添付ファイル： 199_LiGang_et_al_2015_SRNU.pdf

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記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：新潟大学理学部  

This paper reports Middle Jurassic radiolarians observed in etched surfaces of chert clasts within conglomerates of the Itsuki Formation of the Itoshiro Subgroup (Tetori Group) in the Taniyamadani Valley, Fukui Prefecture, central Japan. This is the first report of Middle Jurassic chert clasts within the Tetori Group. Middle Jurassic cherts were included in late Middle Jurassic and younger accretionary complexes in East Asia on the basis of previous studies. This study indicates that late Middle or younger accretionary complexes had been exposed and denuded in the provenance of the Tetori Group by the depositional time of the Itsuki Formation.

添付ファイル： 198_Ito_et_al_2015_SRNU.pdf

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Wiley-Blackwell Publishing Asia  

Abstract: Defining the Jurassic-Cretaceous boundary is a controversy in stratigraphic study of the world. It has been widely accepted that this boundary can be defined at the bottom of Berriasian in Tethys, with the appearance of the ammonite Berriasella jacobi dating to ca. 145 Ma. However, it is difficult for the widespread terrestrial deposits in China to correlate with the international standard of marine facies. The Somanakamura Group in Japan is represented by a succession of marine-continental transitional strata. It provides a bridge of marine and nonmarine stratigraphic correlation. The ammonite and radiolarian fossils preserved in this group suggest an age from Bajocian to early Valanginian. The J-K boundary was defined in or atop the Tomizawa Formation of the group according to the ammonite data. The present authors study the fossil spores and pollen newly found from the Tomizawa and Koyamada formations. Three assemblages have been recognized. They are Assemblage 1 (Cyathidites-Classopollis) from the upper part of the Tomizawa Formation, Assemblage 2 (Cyathidites-Jiaohepollis) from the lower part of the Koyamada Formation, and Assemblage 3 (Cyathidites-Spheripollenites-Ephedripites) from the middle to upper part of the Koyamada Formation. With the reference of ammonite evidence, the J-K boundary can be defined between Assemblage 1 and Assemblage 2. This palynological J-K boundary can be correlated with that of terrestrial sequence in China. However, local biostratigraphy imply that the continental J-K boundary in China is of 135 or 137 Ma age. It has a considerable discrepancy from the marine standard. Biogeographically, the distribution pattern of spores and pollen in southern China is in accordance with that in the Somanakamura Group, which parallels the Tuchengzi Formation in northeastern China. By the palynological correlation between the Somanakamura Group and the strata in southern China, and then with the sequence in northeastern China, it is suggested that the continental J-K boundary is located in the Tuchengzi Formation.

DOI： 10.1111/1755-6724.12411

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記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：新潟大学理学部  

Well-preserved radiolarians were extracted from a siliceous mudstone pebble within conglomerate of the Mizukamidani Formation of the Tetori Group in the Itoigawa area, Niigata Prefecture, central Japan. These radiolarians correspond to the assemblage of the Middle Jurassic (Striatojaponocapsa plicarum Zone (JR4): Bajocian to early Bathonian). Based on general features of an accretionary complex and previous knowledge of the surrounding geological units in East Asia, the Middle Jurassic (JR4) siliceous mudstone was derived from the latest Middle or Late Jurassic accretionary complexes. This result indicates that the latest Middle or Late Jurassic accretionary complexes had been exposed and denudated in the depositional time of the Mizukamidani Formation.

添付ファイル： 188_Ito_et_al_2014_SRNU.pdf

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：GEBRUDER BORNTRAEGER  

The definition of the Global Boundary Stratotype Section and Point (GSSP) of the Bathonian/Callovian (Middle Jurassic) boundary is under debate in Europe. The sections that include the Bathonian/Callovian boundary are still limited in East Asia. In Japan, the Middle Jurassic Kaizara Formation, which is located within the Tetori Group, is exposed in Fukui Prefecture, central Japan. This formation contains abundant ammonite fossils. On the basis of ammonite fossils, the Kaizara Formation has been assigned to the late Bathonian to early Callovian age. Therefore, the Kaizara Formation is an important formation encompassing the Bathonian/Callovian boundary in East Asia. However, the fossil-bearing horizons have not been observed clearly in previous studies. In the present study, a detailed analysis of the molluscan fossil-bearing horizons of the Kaizara Formation was conducted utilizing three stratigraphic successions. On the basis of seven identified genera and nine species of ammonites, the presence of three successive assemblage zones first proposed by a previous study is confirmed: the Pseudoneuqueniceras yokoyamai, the Kepplerites japonicus, and the Oxycerites assemblage zones. Of these, the Pseudoneuqueniceras yokoyamai Assemblage Zone was assumed to correspond to the Orbis - Oppeli Zone (late Bathonian), and the Kepplerites assemblage Zone was assumed to be comparable to the early Callovian age. These results indicate that the Bathonian/Callovian boundary lies within the middle part of the Kaizara Formation.

DOI： 10.1127/0078-0421/2014/0048

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

Recent studies on the global distribution of Pliensbachian and Toarcian polycystine radiolarians allowed us to examine faunal turnovers and the biogeography through this critical time interval around a major ecologic and biotic crisis. The analysis is based on the distribution of 167 species belonging to 69 genera. Significant variations in the ratio between the number of originating and extinct species have been recognized. During the early Early Pliensbachian FADs greatly exceeded LADs and the maximum diversity was reached in the late Early Pliensbachian. The trend then reversed with the number of LADs exceeding FADs throughout the Late Pliensbachian and Early Toarcian (extinction interval). Recovery started in the Middle and Late Toarcian, when the number of FADs again surpassed the number of LADs.
Three differing evolutionary patterns are observed amongst radiolarian genera through the studied time interval. The largest group diversified rapidly in the Early Pliensbachian and experienced higher extinction rates in the Late Pliensbachian and Early Toarcian; a second group exhibited no major changes; and a third group of mainly spongy spumellarians was successful during the extinction interval. The overall trend of radiolarian diversity is in a fairly good agreement with that of other marine faunas (ammonites and also benthos), but shows an inverse correlation with diversity trends of phytoplankton.
Correlation with concomitant environmental changes indicates that radiolarian radiation/extinction rates were not consistently linked with temperature fluctuations or sea-level changes. It is also evident that the diversity decrease started well before the Early Toarcian negative delta C-13 peak and the Oceanic Anoxic Event (OAE). The extinction interval corresponds well to the duration of a short-term anomaly in the strontium-isotope record, including the rapid decrease of Sr-87/Sr-86 values in the Late Pliensbachian as well as the rapid increase in the Early Toarcian. This coincidence supports the hypothesis that the predominance of extinctions over originations was caused by a series of climate and environmental changes related to intensified magmatic activity.
Some distinct biogeographic differences have been observed. Generic differences are most strongly displayed by the presence or absence of a particular genus or by changes in abundance while species differences range from greater variability to having completely different species in separate palaeolatitudinal realms. Two groups of genera are distinguished: those that are common to abundant in the Tethys (low latitudes) and rare to absent in mid to high latitudes, and those common to abundant in mid to high latitudes and rare to absent in the Tethys. (C) 2013 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.palaeo.2013.06.028

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：CHINA UNIV GEOSCIENCES  

The Gujingling Section in Xiaodong, Guangxi Zhuang Autonomous Region, China, consists of cherts and siliceous siltstones, which belongs to the Bancheng Formation of the Qinzhou allochthon. Three successive radiolarian assemblage-zones related to the Guadalupian (Middle Permian) appear in the section in the following ascending order: Pseudoalbaillella sp. aff. Pseudoalbaillella longicornis-Pseudoalbaillella fusiformis, Follicucullus monacanthus, and Follicucullus scholasticus-Follicucullus porrectus. The radiolarian content in this section is generally greater than that of sponge spicules. The radiolarian fauna commonly consists of abundant Albanlellaria and spherical radiolaria with minor Latentifistularia and Entactinaria. The sponge fauna is composed mainly of hexactinellids with minor demosponges. These siliceous fossil faunal features, comparable with those in a deep basin of the western belt of the Phosphoria Basin in the western United States, indicate that the Bancheng Formation in the Gujingling Section was deposited in a basin deeper than 1 000 m. The siliceous siltstones in the section are characterized by inclusion of silt-sized quartz and no inclusion of sand-sized materials, suggesting that the Gujingling Section was located at least a few hundred kilometers from the South China Block in the Guadalupian.

DOI： 10.1007/s12583-013-0317-2

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記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：新潟大学理学部  

Restudy of the type species of Tylestheria from the First Member of the Upper Cretaceous Nenjiang Formation in Nenjiang County, north-east China under a scanning electron microscope (SEM) revealed morphological features on the carapace that had not been recognized previously: growth lines with serrated lower margins; growth bands near the umbo and in the middle part of the carapace with intercalated fine reticulation between relatively widely spaced radial lirae; growth bands in the ventral part of the carapace ornamented with radial lirae and punctae. According to the recent radiometric dating and magnetostratigraphic data of the Late Cretaceous deposits in the Songliao Basin, the Tylestheria-bearing horizons of the Nenjiang Formation (Songliao Basin) and the Majiacun Formation (dinosaur egg bearing Xixia Basin, Henan) were revised to be late Santonian in age.

添付ファイル： 183_LiGang_Matsuoka_2013_SRNU.pdf

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記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：新潟大学理学部  

The Zhongba melange along the Yarlung‒Tsangpo suture zone, southern Tibet, is composed mainly of red bedded chert and sandstone in addition to subordinate mudstone with blocks of augite peridotite, gabbro, basalt, limestone, and chert. The chert from the melange yields well-preserved radiolarian fossils that can be assigned to the Hsuum maxwelli zone (JR 7) of Kimmeridgian (Late Jurassic) age. This evidence enables the biostratigraphic age determination of this melange. The radiolarian assemblage is older than microfossils previously reported from this melange.

添付ファイル： 181_LiXin_et_al_2013_SRNU.pdf

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記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：新潟大学理学部  

Middle Permian (Guadalupian) radiolarians were obtained from bedded siliceous rocks collected from the Gufeng Formation in the Liuhuang section in Chaohu, Anhui Province, South China. Three radiolarian assemblages, named as Pseudoalbaillella fusiformis, Follicucullus monacanthus, and Ruzhencevispongus uralicus, were recovered from the Liuhuang section in an ascending stratigraphic order. The quantitative analysis of radiolarian fauna in the Liuhuang section shows the following characteristics. Albaillellarians and spherical radiolarians occurred more commonly than stauraxon radiolarians, in the lower part; spherical radiolarians are extremely dominant in the middle part; and spherical and stauraxon radiolarians dominate the upper part. In other words, albaillellarians decrease upward in the Liuhuang section, whereas stauraxon and spherical radiolarians increase. This vertical radiolarian faunal change has been reported from the Gufeng Formation in other sections and areas in the Lower Yangtze region. Our findings are in keeping with previous reports, which supports a conclusion that radiolarian faunal change is common throughout the Gufeng Formation in the Lower Yangtze region.

添付ファイル： 182_Ito_et_al_2013_SRNU.pdf

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Society for Science on Form  

We investigated two geometrical models of skeleton forms of spherical radiolaria. Both models are based on Voronoi tessellation of given points on a sphere. We allocate a given number of points called "generators", which can be related to pore frames, and obtained their Voronoi tessellation and approximated polyhedron. The first model is based on random allocation of generators, and the second one is based on global minimization of a potential function whose value is calculated from a generator distribution. Depending on the types of these generator distributions, we obtained different types of approximated polyhedrons. Using these polyhedrons, we analyzed the frequency distributions of the number of vertices of the polygons and the total edge lengths. We then compared the polyhedrons derived by the tessellation with real radiolaria. A comparison of frequency distributions revealed that the first model is not sufficient for mesh-like radiolaria. However, the second model had similar distribution to that of another type of spherical radiolaria which has almost regular structure. Under the condition of same number of generators, the second model produces approximately 6 percent smaller total edge length than the first model.

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：The Geological Society of Japan  

中期更新世の日本海における環境変遷を明らかにするため，新潟県佐渡島に分布する沢根層上部の貝形虫化石を氷期−間氷期スケールで検討し，中期更新世に日本海表層〜浅海域が低塩分化した証拠を浅海層で初めて確認した．沢根層上部の堆積場は水深150〜200 m前後で変化し，低海水準期により浅く寒冷・低塩分な環境を示した．また，高海水準期でも暖流の影響が認められないことから，沢根層上部は亜間氷期から氷期に至る氷河性海水準変動を記録していると推察される．氷期の低塩分を示唆する貝形虫化石群集は，単位gあたりの個体数が少なく，後期鮮新世〜現在の地域的な低塩分環境を示唆する群集と異なること，低塩分環境に優占する2種は亜間氷期には全く産出せず，日本海の低塩分環境を生き延びた種の生息環境と類似する環境に現生していることから，沢根層上部には中期更新世以降に日本海で起こった氷期の表層水低塩分化が記録されていると考えられる．

DOI： 10.5575/geosoc.2012.0024

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その他リンク： https://jlc.jst.go.jp/DN/JALC/10009088671?from=CiNii

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

Nylon models of earliest Cretaceous Pantanellium were produced from a real fossil specimen by applying X-ray micro-CT and layered manufacturing technology. These models enable us to elucidate the exact number of polygonal pore frames and their configuration on the cortical shell, which is difficult to recognize from scanning electron microscope or light microscope images. The specimen has a total number of 27 polygonal (12 pentagonal and 15 hexagonal) pore frames. The pore frame number and the configuration are important criteria in the taxonomy of the Family Pantanelliidae. Planar graphs showing the distribution of polygonal pore frames on the cortical shell are depicted. They are expected to be a standard method for presenting and examining geometrical characters of pantanellid cortical shells. The new technology of X-ray micro-CT can shed light on detailed morphological examinations of not only radiolarians but also any other microfossils. (C) 2012 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.marmicro.2012.02.005

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SPRINGER  

Cyanobacterial symbionts were detected in the extracytoplasm of the polycystine radiolarian Dictyocoryne profunda Ehrenberg. The bacterial symbionts were observed as numerous spherical bodies similar to 0.5-1.0 mu m in diameter under transmission electron microscopy. They were present in a very restricted location close to the periphery of the host radiolarian shell, adjacent to the central capsular wall. Several cells of them may have been in the process of cell division or just divided. The symbionts had thylakoid-like structures, which ran around the cell periphery in two or three concentric layers. Based on the small subunit ribosomal DNA (16S rDNA) phylogenetic analyses, the intracellular symbiotic bacteria grouped with cyanobacteria belonging to the genus Synechococcus. Three sequences, one from each of three specimens of D. profunda, collected in March/October 2009 and March 2010 from the East China Sea, were the same and branched within Synechococcus clade II, that is characterized by strains with low amounts of phycourobilin (PUB).

DOI： 10.1007/s13199-012-0174-2

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

添付ファイル： 178_Ito_et_al_2012_J.pdf

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記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：新潟大学理学部  

Jurassic deposits in China are mainly of continental origin and contain an abundance of clam shrimps, whose rapid evolution and radiation make them biostratigraphically useful in subdividing and classifying non-marine strata in China. In this paper we summarize nine Jurassic clam shrimp faunas in China. Although the early Middle Jurassic Shizhuestheria fauna has been encountered in geographically small areas in Chongqing, the early Early Jurassic Palaeolimnadia baitianbaensis fauna, the late Early Jurassic Eosolimnadiopsis fauna and the Middle Jurassic Euestheria ziliujingensis fauna are widely distributed in southern and northern China. Since late Middle Jurassic because of the climate change and the geographical barrier clam shrimps began to differentiate into two geographical provinces, e.g. the Paleoleptestheria? chinensis fauna in southwestern China and the Sinokontikia fauna in northern China. During Late Jurassic warm, extremely arid climate in China made clam shrimps differentiated into three faunas, e.g. the Oxfordian Pseudograpta fauna of the northern province, the Oxfordian-Kimmeridgian Eosestheriopsis fauna and the Qinghaiestheria-Mangyalimnadia fauna of the southern province, the latter fauna is only recovered in one locality in the Qaidam Basin.

添付ファイル： 171_LiGang_Matsuoka_2012_SRNU.pdf

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記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：新潟大学理学部  

A specimen of fossil fish was obtained from the Sakuraguchidani Mudstone Member of the Nishinakayama Formation, the Toyora Group. The fossil-bearing horizon, 23-1, is laminated black mudstone with abundant fossil woods and pyrite granules. On the basis of ammonoid biostratigraphic research, this horizon corresponds to the base of the Harpoceras inouyei Zone, which is correlated to the base of the Exaratum Standard Subzone, middle part of the Lower Toarcian. The present specimen, one of rare occurrences of fish vertebrae, could contribute to tracing the evolutionary history of Early Jurassic fish in the Panthalassa.

添付ファイル： 170_Nakada_Matsuoka_2012_SRNU.pdf

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

添付ファイル： 177_Sakai_et_al_2012_J.pdf

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：GEBRUDER BORNTRAEGER  

The Toyora Group, Jurassic continental shelf sediments exposed in southwest Japan, is divided into three formations. The lower member of the Nishinakayama Formation, the middle part of the group, is characterized by an abundance of ammonoid fossils. Ammonite zonal schemes have been established, although these frameworks were difficult to correlate with European zonations. This study aims to revise the ammonite zonation of this member and to correlate the new zonal scheme with the European zonations. Four successive ammonoid zones are proposed (in ascending order): the Canavaria japonica Zone, the Paltarpites paltus Zone, the Dactylioceras helianthoides Zone and the Harpoceras inouyei Zone. These new zones are compared to the zonations established in European provinces. The base of the P. paltus Zone corresponds to the Pliensbachian/Toarcian boundary. In the Upper Pliensbachian, the lowermost part of the C. japonica Zone analyzed in this study is correlated with the Apyrenum Subzone. In the Lower Toarcian, the base of the D. helianthoides Zone seems to be compared to a horizon within the Clevelandicum Subzone, and the base of the H. inouyei Zone is correlated with the base of the Exaratum Subzone. The uppermost part is probably compared to the Fibulatum Subzone.

DOI： 10.1127/0078-0421/2011/0006

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

Silicified thin larval bivalve shells occur in Upper Triassic radiolarian chert (Early Norian) in the Liminangcong Formation of the Malampaya Sound Group, part of a Late Jurassic to Early Cretaceous subduction-related accretionary complex in the North Palawan Block, western Philippines. The bivalve-bearing radiolarian chert, which we term "bivalve chert," is considered to be a deep-sea sediment that accumulated in an open-ocean realm of the Panthalassa Ocean. Radiolarian and conodont biostratigraphies indicate an early Norian deposition of the thin-shelled bivalves. The bivalve morphology, thin shells (less than 30 mu m thick), smooth ornamentation, and small size (less than 1.3 mm long), suggests they represent larval shells. Although their taxonomic identity cannot be established with certainty, halobiid bivalves that lived in Norian times apparently had such a planktonic larval mode of life. (C) 2011 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.marmicro.2011.01.005

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記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：新潟大学理学部  

Radiolarians living in surface–subsurface waters (0–200 m depth) were documented from the Japan Sea off Tassha, Sado City, Sado Island, Niigata Prefecture, central Japan on 7 June 2010, along with water properties (temperature, salinity, and fluorescence intensity). Plankton samples were collected from two depth intervals (0–100 m and 100–200 m), and Rose Bengal staining was used to discriminate "living" from "dead" specimens. The temperature ranged from 8.9℃ to 10.5℃ at 100–200 m depth, and from 10.5℃ to 17.4℃ at 0–100 m depth. Salinity shows little variation at depths of 0–200 m, ranging from 34.1 to 33.7 psu. Fluorescence intensity shows a peak at around 54 m depth. The radiolarian fauna of the deeper sample (607-11SD-8; 100–200 m depth), from which 23 "living" and 15 "dead" specimens were obtained, consists mainly of cold-water species such as Larcopyle buetschlii and Cyrtidosphaera reticulata, along with Cladococcus bifurcus, Acanthosphaera circopora, and Phormacantha hystrix. The shallower sample (607-11SD-5; 0–100 m depth) contains 16 "living" and 2 "dead" specimens, including C. reticulata, L. buetschlii, and A. circopora, although the standing stock is very low. The existence of "living" specimens of L. buetschlii and C. reticulata at 100–200 m depth shows that these cold-water species are able to survive in deeper waters (>100 m depth) during the warm season in the central Japan Sea. The depth distributions of other species (e.g., A. circopora) in the subsurface water were also determined, providing ecological information on living radiolarians in the Japan Sea.

添付ファイル： 165_Kurihara_Matsuoka_2011_SRNU.pdf

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：福島県立博物館  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

Skeletogenesis in polycystine radiolarians was detected, using a fluorescent compound called PDMPO (2-(4-pyridyl)-5-[(4-(2-dimethylaminoethylaminocarbamoyl)methoxy)-phenyl] oxazole). This compound binds under acidic conditions with silica in the silica deposition vesicle (SDV) of radiolarians, and only newly added silica emits a green fluorescence under ultraviolet light. We used cells fixed with formaldehyde of two species of spherical Spumellaria (Hexacontium philosophica and Rhizosphaera trigonacantha) and three species of cyrtid Nassellaria (Anthocyrtidium angulare, Clathrocyclas (?) cassiopeiae, and Lophophaena hispida), in which green fluorescence occurred in the entire skeleton outside the endoplasm. In contrast, the conical nassellarian species Eucyrtidium hexagonatum emitted green fluorescence only on the cephalo-thorax-abdominal part of the skeleton, and on part of the inner ring at the segmental suture, and the margins of pores, suggesting partial biological silicification. Two flat spumellarian species (Dictyocoryne profunda and Rhopalastrum elegans) showed bright green fluorescence over the full skeleton in some cells, but other cells did not fluoresce at all, even though young cells in good condition were tested, suggesting that intermittent growth occurs in these species, as known from a controlled incubation experiment. We did not observe development of new skeletons, but "skeletal thickening growth" (STG), defined as silica deposition over the surface of an existing skeleton, occurred to varying degrees in the polycystines, and may result in the formation of lamellar structures, as observed in sectioned skeletons of polycystines. (C) 2010 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.marmicro.2010.08.005

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

Jurassic radiolarians from 220 samples in Queen Charlotte Islands, B.C., Williston Lake, B.C., east-central Oregon, Baja California Sur, southern Spain, Austria, Slovenia, Turkey, Oman, Japan and Argentina were studied in order to construct global zonation for the Pliensbachian, Toarcian and Aalenian stages. Well-preserved faunas from continuous stratigraphic sections in Queen Charlotte Islands provide the most detailed record for this time interval, and all collections are tied to North American ammonite zones or assemblages. Collections from nearly all other areas lack independent dating except for early Toarcian carbon-isotope dating in Slovenia and late Aalenian ammonites in Spain.
A database of 197 widely distributed updated taxonomic species was used to construct a Unitary Association (UA) zonation for the interval. A global sequence of 41 UAs was obtained for the top of the Sinemurian to the base of the Bajocian. The first and the last UAs represent the Late Sinemurian and the Early Bajocian respectively. The remaining 39 UAs were merged into nine zones (four Early Pliensbachian, one Late Pliensbachian, one Early Toarcian, one Middle-Late Toarcian, and two Aalenian) according to prominent radiolarian faunal breaks and ammonite data. The new zones are the Canutus tip pen - Katroma clara Zone (latest Sinemurian/earliest Pliensbachian); Zartus mostleri - Pseudoristola megaglobosa, Hsuum mulleri - Trillus elkhornensis and Gigi fustis - Lantus sixi zones (Early Pliensbachian); Eucyrtidiellum nagaiae - Praeparvicingula tlellensis Zone (Late Pliensbachian); Napora relica - Eucyrtidiellum disparile Zone (Early Toarcian); Elodium pessagnoi - Hexasaturnalis hexagonus Zone (Middle and Late Toarcian); Higumastra transversa - Napora nipponica Zone (early Aalenian); and Mirifusus proavus - Transhsuum hisuikyoense Zone (late Aalenian). These zones can be correlated worldwide and link previously established UA zonations for the Hettangian-Sinemurian and the Middle to Upper Jurassic. The new zonation allows high-resolution dating in the studied interval and provides a solid basis for analyzing faunal turnovers and the paleobiogeography of Jurassic radiolarians. (C) 2010 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.palaeo.2010.08.024

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記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：新潟大学理学部  

The radiolarian fauna on November 13, 2008 is documented from surface-subsurface waters (< 100 m depth) in the Japan Sea off Tassha, Sado City, Sado Island, Niigata Prefecture, central Japan. The sea-water temperature of the water mass from the surface to 100 m depth ranged from 19.4 to 17.1℃. The temperature at 100 m depth (17.1℃) was the highest value in the year-round record from March 2008 to February 2009. Seventeen spumellarian and 20 nassellarian species were identified from 1711 shells. The fauna is characterized by abundant warm-water species, including Tetrapyle octacantha, Spongosphaera streptacantha, Pseudocubus obeliscus, and Didymocyrtis tetrathalamus, along with Acanthodesmia vinculata, Acanthosphaera circopora, and Dictyocoryne profunda group. Given the abundance of T. octacantha and S. streptacantha, the species composition of the November fauna in 2008 is similar to that of September faunas recorded in our previous studies off Sado Island. This finding indicates that the radiolarian fauna inflowing within the Tsushima Warm Current around Sado Island in 2008 was under the influence of the same water current system from September to November, probably the Taiwan-Tsushima Warm Current System. In addition, the common occurrence of warm-water species dwelling in tropical to subtropical surface waters (e.g., D. tetrathalamus) demonstrates the influence of warm waters of the Kuroshio.

添付ファイル： 157_Kurihara_Matsuoka_2010_SRNU.pdf

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記述言語：英語   掲載種別：研究論文（その他学術会議資料等）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：SPRINGER-VERLAG BERLIN  

Blind people can learn about real objects through tactile sensations. However, the objects are sometimes rather small to observe by touch. Enlarged three-dimensional (3D) models for such tiny objects are useful for tactile teaching. This paper presents the first exact models of radiolaria and foraminifera. Their 3D shape data are measured using micro X-ray CT, and their exact 3D models are constructed using layered manufacturing. A recognition test showed the immense usefulness of these enlarged models for blind students in learning the shapes of micro-organisms.

DOI： 10.1007/978-3-642-14100-3_78

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：形の科学会  

We propose a simple mathematical model for chamber arrangement of planktic foraminifera. The arrangement is approximated using connection of spheres. It is represented by combination of four sequences: they correspond to radius of chamber, horizontal/vertical distance of connected chambers, and angle of horizontally projected two lines constructed by connection of centers of adjacent spheres. We assumed that the sequences of the radius and horizontal/vertical distances are geometric series and that of the angle is constant. We succeeded in reproducing the chamber configuration of all recent planktic foraminifera at the level of family in taxonomy. We also point out that some other parameters are required in order to classify the chamber arrangement in detail. The model enables us to consider an optimization problem of the volume-surface area ratio which corresponds to the cost of chamber forming materials. Using the simplest case of our models, we obtain an optimized radius-distance relation.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

We present the first record of a living solitary spherical polycystine radiolarian, Haliommilla capillaceum (Haeckel), with a chain of extracellular cells. The extracellular cells divided seven times over about 4 h from the 8-cell to the 1024-cell stage and then swam away. At the 1024-cell stage the cells were very small, isospores (ca. 12 mu m in length). After final cytokinesis, the cells remained essentially immobile, with only occasional movement. After this immobile stage, they abruptly swam out in a burst into seawater. The cell division patterns and cell shape are similar to the sporogenesis of the host-specific parasitic dinoflagellate Duboscquella sp. infecting a tintinnid. Precise identification, however, needs molecular analysis, transmitted scanning images and proliferation test. (C) 2009 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.marmicro.2009.04.007

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：土木学会  

We discussed the evolution of the skeleton of radiolaria (marine plankton) from a viewpoint of optimization process of frame structure. The genus Mirifusus, a group of Mesozoic radiolaria, has a character of detailed and geometric frame between segments. The geometric framework was evolved from combination of pentagon and rhombus to triangle through pentagon. We treated such frameworks as two dimensional rigid frames with periodic boundary condition. We obtained normalized displacement of upper-side under the condition of compress or tortional force for each framework. The results show that the triangle structure is most effective if the 2-D frame is applied both of compress and torsional forces in most cases. Such a structure corresponds to final frame structure of genus Mirifusus during its evolution process.

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その他リンク： http://hdl.handle.net/10191/24759

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：The Geological Society of Japan  

群馬県神流町瀬林地域に分布する山中白亜系瀬林層上部層から，21属25種の二枚貝化石およびアンモノイド化石からなる軟体動物化石群集が産出した．この軟体動物化石群集は<i>Neithea matsumotoi</i>などを含み，アルビアン階とされる九州の先外和泉層群八代層からの二枚貝群集との共通性が高く，テチス型動物群であると見なされる．アンモノイド群集は<i>Crioceratites</i>（<i>Paracrioceras</i>）<i>asiaticum</i>を含みバレミアン階を指示する．従来，八代層に特有とされていた二枚貝化石は，その産出レンジがバレミアン階まで下りることが明らかになった．山中白亜系の物部川層群相当層からテチス型動物群が産出したことは，横ずれ断層による下部白亜系の構造的再配列だけでは古生物地理を説明できないことを示している．また，瀬林層は，海水温が高くなった環境で堆積したと考えられる．

DOI： 10.5575/geosoc.115.130

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その他リンク： https://jlc.jst.go.jp/DN/JALC/00329117793?from=CiNii

記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：新潟大学理学部  

This paper documents a radiolarian fauma in late winter (March 10, 2008) within surface subsurface waters (<100 m depth) in the Japan Sea off Tassha, Sado City, Sado Island, Niigata Prefecture, central Japan. The sea-water temperature at the sampling site (38°05' N, 138°10' E) is near-constant down to 100 m depth (9.6-9.7℃), which probably represents the lowest water temperature throughout the year. This water body with a uniform temperature is considered to have formed by the development of a surface mixed layer influenced by the strong northwesterly winter monsoon on the Japan Sea. Eleven spumellarian and 14 nassellarian species were identified from 583 recovered skeletons. The faunal composition is characterized by the dominance of cold-water spumellarians (Cyrtidosphaera reticulata and Larcopyle buetschlii) and spicule-type nassellarians (Neosemantis distephanus and Plectacantha cremastoplegma) with minor amounts of a warm-water dweller (Didymocyrtis tetrathalamus). Based on accumulated knowledge of the radiolarian ecology of living species off Sado Island, these findings can be explained in terms of the low water temperature preferred by cold-water species, the opportunistic appearances of spicule-type nassellarians, and weak inflow of the Tsushima Warm Current during winter.

添付ファイル： 146_Kurihara_Matsuoka_2009_SRNU.pdf

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

添付ファイル： 144_Matsuoka_2009_NOM.pdf

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

添付ファイル： 145_Kokubo_Matsuoka_2009_NOM_J.pdf

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

2-(4-pyridyl)-5-[(4-(2-dimethylaminoethylaminocarbamoyl)methoxy)-phenyl] oxazole (PDMPO) is a fluorescent compound that accumulates in acidic cell compartments. PDMPO is accumulated with silica under acidic conditions, and the newly developed silica skeletons show green fluorescent light. This study is the first to use PDMPO in polycystine radiolarians, which are unicellular planktonic protists. We tested Acanthodesmia sp., Rhizosphaera trigonacantha, and Spirocyrtis scalaris for emission of green fluorescence. Entire skeletons of Acanthodesmia sp. and Sr. scalaris emitted green fluorescent light, whereas only the outermost shell and radial spines of Rz. trigonacantha showed fluorescence. Two additional species, Spongaster tetras tetras and Rhopalastrum elegans did not show fluorescence. Green fluorescence of the entire skeleton is more like the "skeletal thickening growth" defined by silica deposition throughout the surface of the existing skeleton. The brightness of the fluorescence varied with each cell. This difference in fluorescence may reflect the rate of growth in these cells. Green fluorescence in PDMPO-treated polycystines suggests the presence of similar metabolic systems with controlled pH. The results of this study shed light not only on the feasibility of using PDMPO in diatoms and siliceous sponges, but also in polycystines. Further application of PDMPO could refine polycystine skeletogenic hypotheses and offer new insight on the physiological functions of silica assimilation. © The Plankton Society of Japan.

DOI： 10.3800/pbr.4.89

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：PUBLICATIONS SCIENTIFIQUES DU MUSEUM, PARIS  

The catalogue of Mesozoic radiolarian genera is a revision of all described genera with re-illustration of their type species. This project was organized under the auspices of the International Association of Radiolarian Paleontologists (Inter-Rad), and was carried out by the Mesozoic Working Group. This is the second of two contributions, this one devoted to the Jurassic-Cretaceous period. It contains 581 genera with re-illustration of their type species. This part shares 30 genera in common with the Triassic catalogue, most of which arose in the Carnian, Norian and Rhaetian. The sharp difference manifested between the Triassic fauna and the Jurassic-Cretaceous fauna is so evident that it justifies two independent catalogues. A comparable division between the Jurassic and Cretaceous could not be justified however, because of the similarity of the fauna, and by the greater number of genera crossing the Jurassic-Cretaceous boundary which is three times that for the Triassic-Jurassic boundary. A distinct characteristic of Jurassic-Cretaceous genera is the high number of nomina dubia (up to 131), contrary to the low number in the Triassic interval. This reflects, in part, the influence of Haeckelian taxonomy in earlier research on Jurassic-Cretaceous faunas prior to the application of SEM techniques. The Mesozoic Working Group has carefully reviewed and re-examined the taxonomy of all available genera, their family assignment and stratigraphic ranges. Following careful comparisons, 91 genera were declared as synonyms. The review has noted 26 homonyms which were duly notified to their corresponding authors, and were corrected previous to the publication of this catalogue. In spite of this effort, unfortunately nine homonyms still remain. Two invalid nominal genera, and two nomina nuda are also reported. The systematic revisions have validated 341 genera for the Jurassic-Cretaceous interval. At the end of this catalogue 24 additional are resented as support for those genera having a poor photographs p original illustration of the type species.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：PALAEONTOLOGICAL SOC JAPAN  

Light microscopic studies, using both video imaging and normal camera, were made on living nassellarian radiolarians Eucyrtidium hexagonatum Haeckel, Pterocotys zancleus (Muller) and Dictyocodon prometheus Haeckel from the East China Sea off Okinawa Island, Japan. Continuous and careful observations revealed pseudopodial activity related mostly to feeding behavior. The results are presented in detail with the definition of 11 descriptive terms for nassellarian pseudopodia. Among them, terminal projections (TP) extending as straight projections from the aperture of the shell body and forming a conical structure (terminal cone: TC) and axial projections (XP) prolonged outward from the center of the aperture and proximally surrounded by TP are used for feeding. Although there are some minor differences, feeding activities of the three species can be subdivided into the following three cyclic phases; Phase I characterized by gradual extension of TP and XP from the aperture, Phase 2 marked by an abrupt withdrawal of TP and XP toward the aperture to engulf captured prey, and Phase 3 during which entangled TP used for capturing prey are completely retracted into the aperture. These lines of evidence suggest that the shell aperture plays the same role of a feeding apparatus as does a mouth. Interestingly, XP of E. hexagonatum sometimes shows abnormal branching, fusion and separation, which is different from the spumellarian axotlagellum.

DOI： 10.2517/1342-8144-12.3.209

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記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：新潟大学理学部  

To assess the influence of the Tsushima Warm Current (TWC) on radiolarian inflow to the Japan Sea, we determined the faunal characteristics and water properties (temperature, salinity, density, and fluorescence intensity) of surface-subsurface waters shallower than 100m depthe in the Japan Sea off Tassha, Sado Island, central Japan on June 4, 2007. Compared with the water properties measured in June 2005, a thick temperature-stratified layer of 16.0-16.6℃ was recorded in water shallower than 32m in June 2007, indicating that the flow force of the TWC had increased in June 2007 relative to that in 2005. This finding is independently supported by broad-based hydrographic data from the Japan Sea. Although the standing stock is very low, the radiolarian fauna consists of typical cold-water dwellers (Larcopyle butschlii, Cyrtidosphaera reticulata, Spongotrochus glacialis) throughout waters shallower than 100m depth, along with a warm-water species (Spongosphaera streptacantha) that usually occurs in summer around Sado Island. Based on the compiled radiolarian faunal and temperature data, S. streptacantha can be considered a typical inflowing species transported by the TWC.

添付ファイル： 140_Kurihara_et_al_2008_SRNU.pdf

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：日本地質学会  

Two rudist taxa, Epidiceras speciosum (Munster) and Monopleura sp. were discovered from the allochthonous Torinosu-type limestone blocks in the Oriai Formation of the Imaidani Group in the Shirokawa area, Southwest Japan. The occurrence of Epidiceras speciosum, indicating a late Kimmeridgian to early Valanginian age, is consistent to the previous age assignment based on the occurrences of middle Kimmeridgian to early Tithonian ammonites (Hybonoticeras) from the overlying Nakatsugawa Formation and the Tithonian radiolarian assemblage of the Imaidani Group. These limestone blocks were thus originally deposited in a shallow marine shelf in the late Kimmeridgian-early Tithonian, and were transported into a deeper environment of shelf slope in the early Tithonian. Monopleura sp. from the Shirokawa area possibly represents the earliest record of this genus and family. The occurrence of Late Jurassic rudists in Torinosu-type limestone suggests that rudists had already expanded globally and that a tropical-subtropical condition prevailed in the shallow marine shelf of East Asia, where the Torinosu-type limestone was deposited at that time.

DOI： 10.5575/geosoc.113.500

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その他リンク： http://hdl.handle.net/10191/6272

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：BIRKHAUSER VERLAG AG  

Environmentally controlled studies on living radiolarians, especially on their feeding mechanisms are rare. In the same way, feeding behaviours of fossil radiolarians are poorly known. In this work, techniques for living radiolarian research, including plankton sampling at sea, observations using different types of microscopes, and laboratory culture, are introduced. Light microscope, epifluorescence microscope, and confocal laser scanning microscope images of selected radiolarian species are presented. Four types of feeding behaviour which correspond well to skeletal morphology are recognized and discussed. Multi-segmented nassellarians, represented by Eucyrtidium, Pterocorys, and Spirocyrtis, take relatively large prey, including ciliates and flagellates. Some other nassellarians, e.g. Pseudocubus and Arachnocorallium, are advantageous in collecting tiny prey including microflagellates and bacteria. Solitary spumellarians, represented by Diplosphaera, Spongosphaera, and Spongaster, also gather tiny prey. Colonial radiolarians such as Collozoum and Buccinosphaera seem to live exclusively on symbiotic algae. The wide variation in feeding behaviour means that radiolarians occupy several kinds of ecological niches in marine environments. Assuming that the radiolarian skeletal morphology indicates their feeding strategy, living forms can give some light on the feeding mechanisms of similar Mesozoic forms. By contrast, the unique curved conical skeleton of the Paleozoic Albaillellaria, unknown after the end-Permian mass extinction, suggests a different feeding behaviour.

DOI： 10.1007/s00015-007-1228-y

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

Middle Jurassic polycystine radiolarian species belonging to the genus Striatojaponocapsa show major morphological changes in the basal structure of the test, overall shell size and shape, and the developmental state of irregular polygonal pore frames. Striatojaponocapsa species also vary widely in the number and arrangement pattern of longitudinal plicae. Striatojaponocapsa plicarum (Yao), with a large basal appendage, gave rise to S. synconexa O'Dogherty, Gorican, and Dumitrica, characterized by reduced basal appendage size and a circular depression. Specimens of the S. plicarum-synconexa species group (S. plicarum and S. synconexa) and S. conexa (Matsuoka), with fewer or highly irregular plicae, were relatively atypical and their morphology can be explained by intraspecific variation. The S. plicarum-synconexa species group gradually increased in overall shell size and had a very distinct lumbar stricture in particular horizons. Striatojaponocapsa conexa became more elongated over time; the stricture of this species became indistinct over time. The remaining species, S. riri O'Dogherty, Gorican, and Durmtrica, evolved from S. conexa and developed more than 42 irregular polygonal pore frames in the middle of the S. conexa zone. The stratigraphic distributions of Striatojaponocapsa reflect two evolutionary lineages: S. plicarum continuously and gradually changed into S. synconexa, then S. synconexa was rapidly replaced by S. conexa in a phyletic evolutionary, process. After S. conexa gave rise to S. riri, the former coexisted with small numbers of the latter, showing cladogenetic speciation. (c) 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.marmicro.2006.11.001

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：新潟大学  

The vertical distribution of radiolarian faunas on September 28, 2005 and the temperature, salinity, density, and fluorescence intensity profiles are documented from surface and subsurface waters (> 100m deep) in the Japan Sea, off Tassha, Sado City, Sado Island, Niigata Prefecture, central Japan. The features of the water mass structure shallower than 100m deep are distinguished by gentle gradients of temperature and salinity in waters between 100m and 20m deep (the lower layer: LL) and a homogeneous temperature and salinity (24.0℃, 32.9psu) in waters shallower than 20m (the upper layer: UL). The species composition of the deeper fauna (ca. 77-54m) is characterized by the abundant occurrence of Acanthosphaera actinota, Pseudocubus sp. A, Lophospyris sp., and Acanthodesmia sp. It is also noteworthy that each species in the deeper water fauna does not exceed 20％. In the shallower fauna (ca. 35-0m), Spongosphaera streptacantha, Pseudocubus obeliscus, and Pseudocubus sp. A comprise 87.5％ of the fauna. Considering the characteristics of vertical water properties, high standing stocks of these three species are likely caused by their temperature preferences and adaptive strategies for a summer environment in the Japan Sea. There is a slight difference in species composition between September faunas of 2000 and 2005 which is probably related to the Tsushima Warm Current (TWC). It is known that the flow force of the TWC varies in 2 to 3- and 10-year cycles, so the TWC fluctuation may influence the annual variation of the fauna around Sado Island.

添付ファイル： 137_Kurihara_et_al_2007_SRNU.pdf

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1155/2007/27894

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：BIOMED CENTRAL LTD  

Background: There is no effective method to obtain genome information from single-celled unculturable organisms such as radiolarians. Even worse, such organisms are often very difficult to collect. Sequence analysis of 18S rDNA has been carried out, but obtaining the data has been difficult and it has provided a rather limited amount of genome information. In this paper, we have developed a method which provides a sufficient amount of data from an unculturable organism. The effectiveness of this method was demonstrated by applying it to the provisional classification of a set of unculturable organisms ( radiolarians).
Results: Dendrogram was drawn regarding the single-celled unculturable species based on the similarity score termed PaSS, offering a consistent result with the conventional taxonomy of them built up based on phenotypes. This fact has shown that genome profiling-based technology developed here can obtain genome information being sufficient for identifying and classifying species from a single-celled organism.
Conclusion: Since this method is so simple, general, and yet powerful, it can be applied to various organisms and cells, especially single-celled, uncluturable ones, for their genome analysis.

DOI： 10.1186/1471-2164-7-135

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

Within the holoplanktonic protists group Radiolaria, the Class Phaeodarea is today represented by several hundreds species. The phaeodarian skeletons consist of opaline silica as well as organic matter and are very fragile and vulnerable to dissolution. Their tests are therefore rarely found in the fossil records; this has caused uncertainty with regard to their phylogenetic evolution. In this study, small, solitary phaeodarian species, namely, Protocystis xiphodon (Haeckel), Challengeron diodon Haeckel and Conchellium capsula Borgert were examined using molecular techniques in order to clarify the phylogenetic position of the Phaeodarea. The phylogenetic trees obtained from the neighbor-joining, maximum-parsimony and maximum-likelihood methods of analysis showed that all phaeodarians formed a monophyletic group within the Phylum Cercozoa. This result contradicts Haeckel's classical taxonomy, wherein the phaeodarians were grouped along with the polycystines, i.e., nassellarians and spumellarians, and the acantharians under the common name "Radiolaria". Within the cercozoan clade, the Phaeodarea were closely related to the euglyphid and pseudodifflugid testate amoebae and the desmothoracid heliozoans. The tests and skeletons of both the phaeodarians and the euglyphid testate amoebae resemble each other in their chemical composition and construction. The similarities in the morphologic features may suggest that they are sisters as the Phylum Cercozoa in which leading from molecular methods. (c) 2006 Elsevier B.V All rights reserved.

DOI： 10.1016/j.marmicro.2006.01.003

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：新潟大学  

The profiles of water properties and vertical distribution of radiolarian faunas are documented from the surface to subsurface water shallower than 100m deep in the Sea of Japan, off Tassha, Sado City, Sado Island, Niigata Prefecture, central Japan. The temperature from 64m deep to the surface ranges from ca. 12.0°C to 18.0°C. Based on temperature gradient, the water mass can be subdivided into three layers. The surface layer shallower than 21m has a high temperature gradient (2.0°C/10m). This profile indicates that the water mass is in the intermediate condition between the winter to spring and summer seasons. The faunal compositions for three different depth intervals can be summarized as follows: (1) the fauna collected from ca. 90-63m deep is characterized by the abundant occurrences of Cyrtidosphaera reticulata and plagiacanthid and lophophaenid nassellarians, associated with Tetrapyle octacantha, Didymocyrtis tetrathalamus tetrathalamus, and Larcopyle butschlii,(2) the faunas collected from ca. 63-36m and 36-0m deep are similar to those of the deeper fauna but their compositions are quite different; T. octacantha and D. t. tetrathalamus are relatively abundant instead of C. reticulata. For C. reticulata and L. butschlii, there is a close correlation between lowering temperature in the vertical profile and increasing numbers of individuals. This may be caused by their temperature tolerance ranges. In addition, species preferring warm water such as D. t. tetrathalamus comprise a large percentage of the shallower fauna than the deeper. Taken the temperature profile and faunal data together, we conclude that the faunal transition off Tassha is mediated by the influx of warm water dwellers of the Tsushima Warm Current into the surface layer of the water column during spring to summer.

添付ファイル： 130_Kurihara_et_al_2006_SRNU.pdf

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：BLACKWELL PUBLISHING  

The Xialu chert radiolarian fauna is latest Jurassic - earliest Cretaceous in age ( Pseudodictyomitra carpatica zone) and contains many taxa in common with coeval northern hemisphere middle-latitude ( temperate) radiolarian faunas represented by the Torinosu fauna in southwest Japan. Common elements include Eucyrtidiellum pyramis ( Aita), Protunuma japonicus Matsuoka & Yao, Sethocapsa pseudouterculus Aita, Sethocapsa (?) subcrassitestata Aita, Archaeodictyomitra minoensis ( Mizutani), Stichocapsa praepulchella Hori and Xitus gifuensis ( Mizutani). The Xialu fauna is less similar to low-latitude ( tropical) assemblages represented by the Mariana fauna. For this reason, the Xialu fauna is regarded as representative of a southern hemisphere middle-latitude ( temperate) fauna. A mirror-image bi-temperate provincialism to the equator in radiolarian faunas is reconstructed for the Ceno-Tethys and Pacific Ocean in latest Jurassic - earliest Cretaceous time.

DOI： 10.1111/j.1440-1738.2005.00491.x

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：新潟大学  

Shell variability of Pseudocubus obeliscus Haeckel within the early autumn radiolarian fauna collected from the Sea of Japan, off Tassha, Sado Island in 2001 is demonstrated based on detailed scanning electron microscopic observations and comparisons among morphologically varied specimens. Pseudocubus obeliscus has an inverted truncated-pyramidal skeleton consisting of an initial spicule, rings formed by several arches, columellae, and other secondary spines. The initial spicule is comprised of a median bar, an apical spine, a dorsal spine, two primary lateral spines, and an axial spine. The ventral spine and secondary lateral spines are absent. Comparative observations of morphologically varied specimens with reference to highly symmetrical, well-regulated specimens show that morphologic variation in P. obeliscus is caused by the transformation of angles between columellae and a primary ring, shape of the primary ring and columellae, and their combination. In addition, some secondary arches are formed for rebuilding a distorted pyramidal skeleton. Therefore, it is concluded that shell variability is expressed by the skeletal instability of some specific parts and self-organizing formation of secondary arches.

添付ファイル： 122_Kurihara_Matsuoka_2005_SRNU.pdf

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：日本地質学会  

愛媛県城川地域に分布する今井谷層群下相層において,泥岩中に異地性岩塊として混在する含大型化石泥質岩を発見した.含大型化石泥質岩岩塊は,生物擾乱を受けた塊状の砂質シルト岩からなり,腕足類,二枚貝,ウニ,アンモナイトおよび材化石などの大型化石を含む.岩塊は,周囲の泥岩と密着しており,漸移関係は示さない.エッチング処理を施した泥質岩を観察した結果,含大型化石泥質岩岩塊は基質の泥岩よりも粗粒な炭質物を含み,特異的であることが明らかになった.含大型化石泥質岩の初生的な堆積場は,陸棚以浅の浅海環境が想定される.含大型化石泥質岩は,浅海域での斜面崩壊に伴いブロック化し,下相層の形成場であるより深い斜面域の堆積盆へと移動し,泥岩中に混在したものと考えられる.岩塊に含まれるアンモナイトと今井谷層群の年代から,混在化の時期はジュラ紀末期(Tithonian前期)と推定される.

DOI： 10.5575/geosoc.110.146

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その他リンク： http://hdl.handle.net/10191/6271

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：BLACKWELL PUBLISHING ASIA  

Upper Paleozoic to Mesozoic sedimentary sequences of chert (Liminangcong Formation), clastics (Guinlo Formation) and a number of limestone units (Coron Formation, Minilog Formation and Malajon Limestone) constitute the accretionary complex of the North Palawan block, Philippines. Based on chert-to-clastic transitions from different stratigraphic sequences around the Calamian Islands, three accretionary belts are delineated: the Northern Busuanga Belt (NBB), the Middle Busuanga Belt (MBB) and the Southern Busuanga Belt (SBB). The accretion events of these belts along the East Asian accretionary complex, indicated by their sedimentary transitions, began with the Middle Jurassic NBB accretion, followed by the Late Jurassic MBB accretion and the Early Cretaceous SBB accretion. Several limestone blocks that formed over the seamounts became juxtaposed with chert-clastic sequences during accretion. During the Late Cretaceous, accretion-subduction along the East Asian margin subsided bringing tectonic stability to the region. The seafloor spreading during the mid-Oligocene disconnected the entire North Palawan block from the Asian mainland and then migrated southward. The collision between the North Palawan block and the Philippine Island Arc system in the middle Miocene generated a megafold structure in the Calamian Islands as a result of the clockwise turn of the accretionary belts in the eastern Calamian from originally northeast-southwest to northwest-southeast.

DOI： 10.1111/j.1440-1738.2004.00443.x

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

添付ファイル： 121_Matsuoka_2004_NOM_L.pdf

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：新潟大学  

The detailed shell structures of Spongosphaera streptacantha Haeckel collected from the Sea of Japan, off Tassha, Aikawa Town, Sado Island, Niigata Prefecture, central Japan, are described based on high magnification SEM and transmitted light microscopic observations. The shell of S. streptacantha consists of a dodecahedral inner microsphere, spherical latticed outer microsphere, long three-bladed main spines arising from the surface of the outer microsphere, and a surrounding three-dimensional spongiose network. Main spines commonly number six or seven, rarely eight or nine, and the number shows no correlation with the size of the spongiose shell. Results of observations on 19 individuals reveal that the differences between the number and arrangement of the main spines and size, shape, and density of a spongiose shell produce morphologic variations in S. streptacantha. Since variability of the spongiose shell depends largely on the number of the main spines and the crude density of sponge-forming apophyses, morphologic variation of S. streptacantha has much to do with how many main spines arise from the outer microsphere during the early ontogenic process.

添付ファイル： 116_Kurihara_Matsuoka_2004_SRNU.pdf

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：UNIV STUDI MILANO  

The We mei Formation in southern Tibet is a shallow marine sequence accumulated in the northern margin of the Indian subcontinent. It has been dated as Tithonian based on ammonites such as Haplphylloceras strigile (Blanford), Berriasella sp. and Himalayites sp.. Six ammonite specimens were found in the type locality of the Weimei Formation. They include Spiticeras (Spiticeras) spitiense (Blanford), Berriasella sp. and Phylloceras sp.. The occurrence of S. spitiense indicates that the ammonite-bearing portion is assignable to the Berriasian stage. The Jurassic/Cretaceous boundary possibly exists within the Weimei Formation.

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：日本地質学会  

関東山地両神山地域に分布する両神山チャートユニットは,地質図に表現しうる3つのサブユニットに区分される.両神山チャートユニットは全体として,チャート砕屑岩シーケンスが構造的に積み重なったパイルナップ構造を呈している.サブユニット1とサブユニット2のチャートからジュラ紀中世Aalenianを,両サブユニットの珪質泥岩からはジュラ紀中世Bajocian〜Bathonian前期を示す放散虫化石がそれぞれ得られた.復元した海洋プレート層序の比較からは,両神山チャートユニットが秩父累帯北帯の柏木層あるいは橋立層群に起源をもつナップであるとするとらえ方は成立しがたい.両神山チャートユニットに比較可能な秩父累帯の地質体としては,南帯の海沢層と北帯の上吉田層がその候補として挙げられる.

DOI： 10.5575/geosoc.109.324

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その他リンク： http://hdl.handle.net/10191/6269

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：日本地質学会  

Fossil spores and pollen were obtained from the Tetori Group (Itoshiro Subgroup and Akaiwa Subgroup) for the first time. They are composed mainly of fern spores. Identified spores include Appendici-sporites spp., Cicatricosisporites spp., Cyathidites spp., Deltoidospora sp., Osmundacidites sp. and Schizaeoi-sporites spp. Gymnosperm pollen Classopollis sp. was rarely found in the Akaiwa Subgroup. The spore and pollen assemblage from the Akaiwa Subgroup can be correlated to Hauterivian to Aptian assemblage from the Songliao Basin, China.

DOI： 10.5575/geosoc.109.420

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その他リンク： http://hdl.handle.net/10191/6270

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

In all 29 polycystine radiolarian species were obtained from surface seawater on May 28, 1999, using a plankton-net at one station (Site 990528; 26degrees37'18"N, 127degrees47'35"E) approximately 5 km northwest of Okinawa Island, Japan. In most polycystine radiolarians of the orders Nassellarida and Spumellarida symbiotic algae were observed under light microscopy. The light microscopic (LM) images of the symbionts, however, varied in clarity among individuals because of the variations in microanatomy of the host radiolarian cells. On the other hand, epifluorescence microscopic (EFM) observation easily detected and confirmed the existence of the algal symbionts within the host cytoplasm even in radiolarians such as Dictyocoryne truncatum (Ehrenberg) that include algal symbionts in the depth of the cytoplasm. The chloroplasts of the algal symbionts emitted autofluorescence in ultraviolet irradiation and they appeared red. That is, the autofluorescence images of the chloroplasts can be used to recognize the existence of the algal symbionts within the host radiolarians. Moreover, staining of the symbiont cells with 4',6-diamido-2-phenylindle permitted visualization of the nucleus in the center of the symbiont cell, confirming the existence of living endosymbiotic algae within the polycystine radiolarians. Both the LM and EFM observations of eight polycystine radiolarian species revealed the specific patterns of various host-symbiont associations. (1) The investigated polycystine radiolarians all possess algal symbionts, except for one species, i.e. Dictyocoryne profunda Ehrenberg. (2) The size of the algal symbionts depends on the radiolarian species. The symbionts are largely classified into two types based on the size of their diameters, i.e. about 8-10 mum for the larger group and about 5 mum for the smaller one. (3) The algal symbionts show a variety of locations within the host radiolarian cytoplasm. The types of distribution of algal symbionts may be a useful characteristic for radiolarian taxonomy. (C) 2003 Elsevier B.V. All rights reserved.

DOI： 10.1016/S0377-8398(03)00035-5

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：新潟大学  

Bottom sediments and invertebrate benthic faunas were recovered by dredge sampling at four stations off the Tassha coast of Sado Island in the Japan Sea. Nineteen crustacean and 144 molluscan species were found in the bottom sediments. Among the decapod crustaceans, Australeremus triserratus (Ortmann) was identified for the first time in the Japan Sea. The following nine molluscan species were newly found around Sado Island: Emarginula fragilis Yokoyama, Nodiscala matajiroi Kuroda, Pyreneola semipicta (Sowerby III), Dimiya filipina Bartsch, Spondylus barbatus Reeve, Agatha lepidula Habe, Cycladicama semiasperoides (Nomura), Abrina lunella (Gould) and Pitar japonicum Kuroda and Kawamoto. The grain size analysis revealed that the bottom sediments were classified into two groups: coarse-grained sand at shallower nearshore sites and fine-grained sand at a deeper offshore site. The cluster analysis for the molluscan faunas was concordant to the grain size classification of the sediments.

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記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：新潟大学  

Organic-walled dinoflagellate cyst assemblages which consist of 30 species are reported from the Pleistocene Sawane Formation at Shichiba, Sado Island, Niigata Prefecture, central Japan. Considering the established age of the formation as well as the dinoflagellate cyst datum levels by previous studies, 9 species are judged to be reworked from older sediments, which means that the present assemblages are heavily altered by sediment reworking during their deposition. Such sort of alteration by reworking, frequently observed in some other Late Pliocene-Pleistocene microfossil records at several localities around the Japanese Islands, may be related to intensive land uplift due to the tectonic inversion since the Late Pliocene as well as to eustatic sea level fluctuations that intensified since the Middle Pleistocene.

添付ファイル： 104_Kurita_Matsuoka_2002_SRNU.pdf

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記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：新潟大学  

The early summer radiolarian fauna in surface waters (<70m) off Tassha is characterized by the abundant occurrence of cold-water species such as Larcopyle butschlii Dreyer, Spongotrochus glacialis Popofsky and Cyrtidosphaera reticulata Haeckel associated with subordinate warm-water species. The faunal composition is different from that in late summer which is dominated exclusively by warm water species derived from the Tsushima Warm Current. This suggests that most warm water species cannot survive during the winter season when sea surface temperatures drop to ca. 10 ℃ around Sado Island.

添付ファイル： 102_Matsuoka_et_al_2002_SRNU.pdf

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Radiolarian biostratigraphic research has been carried out along two continuous sections through the Xialu Chert, one of the accreted sheets included in the Yarlung-Zangbo Suture Zone. Six radiolarian zones have been identified as follows: Laxtorum(?) jurassicum Zone (Aalenian), Tricolocapsa plicarum Zone (Bajocian-lower Bathonian). Stylocapsa(?) spiralis Zone (upper Callovian-Oxfordian), Hsuum maxwelli Zone (Kimmeridgian), Pseudodictyomitra carpatica Zone (upper Tithonian-lower Valanginian), and Turbocapsula costata Zone (Aptian). A reconstructed stratigraphy of the Xialu Chert, based on lithological succession and radiolarian dating, indicates that the chert exhibits a long depositional history, at least from early Middle Jurassic (Aalenian) to late Early Cretaceous (Aptian). The separation of the Lhasa Block from the northern Gondwana margin must, therefore, be dated before the Aalenian. The absence of calcareous sediments in the Xialu Chert indicates that the oceanic basin was deeper than the CCD throughout the depositional history. The transition from chert to siliceous mudstone is recorded sometime in Early Cretaceous, most probably around the Barremian/Aptian boundary. This means that the oceanic plate had already started being consumed at a trench by that time. The accretion of the Xialu Chert occurred after the Aptian time. © 2002 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S1367-9120(01)00044-X

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記述言語：日本語   出版者・発行元：日本地質学会  

DOI： 10.14863/geosocabst.2002.0_152_1

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

添付ファイル： 92_Matsuoka_et_al_2001_SRNU.pdf

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：日本地質学会  

ブスアンガ島は, ペルム紀からジュラ紀にわたるチャート(リミナンコン層)とジュラ紀中世から白亜紀古世にわたる砕屑岩類(ギンロ層)から主として構成される付加体(マランパヤサウンド層群)よりなる.マランパヤサウンド層群は, 全体として北に急角度で傾斜する覆瓦構造をなしている.同層群はチャート・砕屑岩シーケンスの剥ぎ取り付加によって形成されたと考えられる.放散虫の生層序学的検討により, チャートから珪質泥岩に移化する層準は, 北から南に向かって系統的に若くなる年代極性をもつことが明らかになった.この年代の違いに基づき, ブスアンガ島のマランパヤサウンド層群分布域を, 北帯, 中帯, 南帯の3帯に区分した.同層群の付加年代は, ジュラ中世から白亜紀古世にわたる.マランパヤサウンド層群は, 西南日本南部秩父テレーンの斗賀野層群に対比される.

DOI： 10.5575/geosoc.107.316

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その他リンク： http://hdl.handle.net/10191/6268

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：A A BALKEMA PUBLISHERS  

An early Middle Jurassic (Aalenian) radiolarian fauna is reported from the Xialu chert in the Yarlung Zangbo Suture Zone. This is the oldest known fossil record from the chert. The fauna comes from a chert sample which contains no terrigenous elements other than clay minerals. This indicates that the Ceno-Tethys was already a rather wide ocean with a pelagic environment far from continents by that time. The rifting and separation of the Lhasa Block from the northern Gondwana margin must have occurred well before early Middle Jurassic time.

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記述言語：日本語   出版者・発行元：日本地質学会  

DOI： 10.14863/geosocabst.2001.0_220_1

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記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：新潟大学  

Abundant occurrence of radiolarians has been observed from the siliceous mudstone of the Tulbuan Plain, Busuanga Island, Palawan Province, Philippines. There are at least 60 species encountered with generally moderate to good preservation. The faunal assemblage is dominated by 2-to 4-segmented smaller nassellarians such as Stichocapsa robusta Matsuoka, Stylocapsa (?) spiralis Matsuoka, Stylocapsa tecta Matsuoka, Tricolocapsa conexa Matsuoka, Dicolocapsa conoformis Matsuoka, Zhamoidellum mikamense Aita. Zhamoidellum ventricosum Dumitrica, Protunuma (?) ochiensis Matsuoka and Sethocapsa funatoensis Aita. Other forms that occur abundantly include Hsuum maxwelli Pessagno gr. Parvicingula dhimenaensis Baumgartner and Orbiculiforma (?) spp. The high occurrence of Stylocapsa (?) spiralis indicates that the assemblage belongs to the S. (?) spiralis Zone or JR6 of Matsuoka (1995). Associated occurrence of Stylocapsa tecta, Dicolocapsa conoformis, Guexella nudata (Kocher) and G. sp. aff. G. nudata narrows down the represented age to the lower part of the S. (?) spiralis Zone which is assignable to late Callovian or early Oxfordian.

添付ファイル： 81_Zamoras_Matsuoka_2000.pdf

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記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：新潟大学  

A radiolarian assemblage was extracted from a siliceous mudstone sample of Triassic shallow marine sequences exposed south of Quxia in the Zhongbei area, Lhaze County, southern Tibet. The radiolarian assemblage discovered in this study is characterized by having abundant spumellarians and few nassellarians. It includes Cryptostephanidium cornigeum Dumitrica, Hindeosphaera spinulosa (Nakaseko and Nishimura), Muelleritortis cochleata (Nakaseko and Nishimura), Pseudostylosphaera goestlingensis (Kozur and Mostler), Pseudostylosphaera hellenica (De Wever), Pseudostylosphaera japonica (Nakaseko and Nishimura), Pseudostylosphaera nazarovi (Kozur and Mostler), Triassocampe sp. cf. T. deweveri (Nakaseko and Nishimura) and Tritortis (?) sp. The faunal association is comparable to that of the TR 4A zone in the Mino Terrane, central Japan, proposed by Sugiyama (1997). The age of the assemblage is assignable to Ladinian (Middle Triassic). Comparison with radiolarian biostratigraphic works in other areas is also concordant with this age assignment.

添付ファイル： 80_YangQun_et_al_2000_SR.pdf

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

A well-preserved radiolarian fauna from a clastic unit of the Khabarovsk accretionary complex (southern part of the Badzhal accretionary wedge terrane in the Russian Far East) is assigned to the basal part of the Pseudodictyomitra carpatica zone. The age of the fauna is most likely late Tithonian. This is the first reliable dating of the clastic unit and makes it possible to constrain the timing of subduction accretion in the Badzhal terrane. The Khabarovsk complex is correlated chronologically with the Bikin and Samarka terranes (Russian Far East), Mino, Southern Chichibu and North Kitakami terranes (Japan), and Nadanhada terrane (northeast China).

DOI： 10.1046/j.1440-1738.1999.00220.x

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：地学団体研究会  

辻堂地域の地質は,東西方向の下多古川断層と南北方向の北角断層により,北部・東部・西部の3地域に区分される.みかけ下位より上位へ,北部地域では四万十帯の槙尾層,赤滝層が,東部地域では四万十帯の伯母谷川層,秩父帯の高原層,山葵谷層,大普賢岳層が,西部地域では四万十帯の宇井層,赤滝層,伯母谷川層が構造的に重なる.各層は緩く北に傾斜したスラストで境される.四万十帯の地質体を精査した結果,宇井層と赤滝層はメランジュを含む地質体であり,産出する放散虫化石から,宇井層はTuronian〜Santonianに,赤滝層はConiacian以降の白亜紀新世に付加体として形成されたと推定される.伯母谷川層と赤滝層,赤滝層と宇井層の境をなすそれぞれのスラストはアウトオブシーケンススラストの可能性がある.伯母谷川層は宇井層および湯川層の一部に,赤滝層は花園層の一部に,宇井層は美山層および湯川層,伯母谷川層のそれぞれ一部にそれぞれ対比される.紀伊山地中央部では秩父帯の地層が欠如するのみならず,本地域の主要部では,四万十帯のなかで構造的最上位に位置する伯母谷川層までも欠如していることが明らかとなった.

DOI： 10.15080/agcjchikyukagaku.52.4_275

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

添付ファイル： 70_Matsuoka_1998_NOM.pdf

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DOI： 10.5575/geosoc.104.634

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記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：新潟大学  

This study reveals that the following zonal marker taxa occur both in the Taman Formation and at the ODP Site 801B section: Acanthocircus dicranacanthos (Squinabol), Hsuum maxwelli Pessagno, Mirifusus guadalupensis Pessagno, Genus Perispyridium Dumitrica, Pseudodictyomitra carpatica (Lozyniak), and Vallupus hopsoni Pessagno and Blome. Six bio-events, such as the first occurrence biohorizon (FOB), the last occurrence biohorizon (LOB) and the evolutionary first appearance biohorizon (EFAB), are commonly identified in the Taman Formation and in the ODP Site 801B section: (1) LOB of Mirifusus guadalupensis Pessagno, (2) LOB of the Hsuum maxwelli Pessagno group, (3) FOB of Vallupus hopsoni Pessagno and Blome, (4) LOB of Genus Perispyridium Dumitrica, (5) EFAB of Pseudodictyomatra carpatica (Lozyniak), and (6) FOB of Acanthocircus dicranacanthos (Squinabol). By using these bio-events, the North American and Japan-Pacific radiolarian zones are correlated with each other. North American Zone 3/Zone 4 and Zone 4/Zone 5 boundaries are situated within the Japan-Pacific Loopus primitivus Zone and Pseudodictyomitra carpatica Zone, respectively. Conversely, the Japan-Pacific Hsuum maxwelli/Loopus primitivus and Loopus primitivus/Pseudodictyomitra carpatica zonal boundaries are situated within North American Zone 3 (Subzone 3α) and Zone 4 (around Subzone 4β /Subzone 4α boundary), respectively.

添付ファイル： 67_YangQun _Matsuoka_1997_SRNU.pdf

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添付ファイル： 66_Matsuoka_Baumgartner_1997_NOM.pdf

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記述言語：日本語   掲載種別：研究論文（その他学術会議資料等）   出版者・発行元：創文  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：海洋出版  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Blackwell Publishing  

This paper contains extended abstracts of the seven papers presented at the symposium 'Radiolarians and Orogenic Belts' held at the seventh meeting of the International Association of Radiolarian Paleontologists (INTERRAD). Important results of the symposium include the following: (1) Upper Paleozoic and Mesozoic cherts are widely distributed within accretionary complexes in the circum-Pacific orogenic belt. Radiolarian dating reveals that long durations of chert sedimentation in a pelagic environment are recorded on both sides of Pacific-rim accretionary complexes (e.g. New Zealand, Japan, Russian Far East, Canadian Cordillera). (2) Triassic radiolarian faunas from New Zealand and the Omolon Massif, northeast Siberia are similar in composition and are characterized by the absence of typical Tethyan elements. This suggests that radiolarian faunal provincialism may have been established as early as the Triassic. High-latitude radiolarian taxa exhibit a bi-polar distribution pattern. (3) The Lower Triassic interval in chert dominant pelagic sequences is mechanically weaker than other levels and acted as a décollement in accretionary events. This lithologic contrast in physical property is considered to reflect radiolarian evolution, such as the end-Permian mass extinction.

DOI： 10.1111/j.1440-1738.1996.tb00026.x

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Elsevier B.V.  

The Vallupinae is a radiolarian subfamily whose range is restricted to the Late Jurassic and the acme in the latest Jurassic (Tithonian). Species of the subfamily (Vallupus group) are found in low- and middle-latitudes of the western Pacific, East Asia, North-Central-South America, and Mediterranean regions. Available paleomagnetic data suggest that Vallupus group-bearing rocks in these localities accumulated within 25° of the Jurassic paleoequator. Seawater temperature is considered to be the major factor controlling the distribution of the Vallupus group. Warm seawater temperatures could be favourable to the propagation of the group. The Vallupus territory is proposed as a water mass inhabited by the Vallupus group. It occupied tropical surface waters from the low-latitude part of the Panthalassa to Tethys. Some Vallupus group-bearing rocks in the Circum-Pacific orogenic belt have been translated from low-latitude depositional sites to higher locations by lateral plate movements. Most Upper Jurassic strata in Japan accumulated outside the Vallupus territory. This means that the Vallupus group cannot be utilized for Upper Jurassic radiolarian zonal correlations between Japan and other regions. However, the rapid speciation of the Vallupus group has a high potential to produce a fine biostratigraphic framework for the Upper Jurassic within the Vallupus territory. © 1995 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/0031-0182(95)00018-6

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Abstract A radiolarian zonal scheme for the entire Jurassic and Lower Cretaceous using biostratigraphic data from both Japanese Island sections and the western Pacific seafloor is documented. The zonation is applicable to low and middle paleolatitude portions of the Paleo‐Pacific ocean. Radiolarian bio‐events such as the evolutionary first appearance biohorizon, first occurrence biohorizon, and last occurrence biohorizon were used to define zones. The 11 zones proposed are, in ascending order, Parahsuum simplum, Trillus elkhornensis, Laxtorum(?) jurassicum, Tricolocapsa plicarum, Tricolocapsa conexa, Stylocapsa(?) spiralis, Hsuum maxwelli, Pseudodictyomitra primitiva, Pseudodictyomitra carpatica, Cecrops sep‐temporatus, and Acanthocircus carinatus zones. Preliminary age assignments for these zones are presented. Copyright © 1995, Wiley Blackwell. All rights reserved

DOI： 10.1111/j.1440-1738.1995.tb00138.x

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記述言語：英語  

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記述言語：英語  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

添付ファイル： 50_Ogawa_et_al_1994_JAMSTEC_L.pdf

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：日本古生物学会  

Discoidal spumellarian species belonging to the Family Spongodiscidae and Porodiscidae float in seawater extending an axoflagellum and numerous axopodia. Observation of their skeletons by scanning electron microscopy (SEM) reveals that they possess a pore larger than openings of the spongiose meshwork in the skeleton surface. The pore is the site through which the axoflagellum projects outward and is named axoflagellum pore. This paper describes some features of the axoflagellum pore of Dictyocoryne truncatum (Ehrenberg), Spongaster tetras tetras Ehrenberg, Spongodiscus biconcavus Haeckel, and Euchitonia elegans (Ehrenberg), showing SEM photos which were taken from different view points on a single specimen. These discoidal spumellarian species float in seawater generally keeping their skeletons horizontal. The position of axoflagellum pore gives useful information on the orientation in floating. This paper draws the orientation of floating D. truncatum and E. elegans. The position and shape of axoflagellum pore differs among species, suggesting that the features of axoflagellum pore can be useful in distinguishing species and in discussing their phylogenetic relationship.

DOI： 10.14825/kaseki.56.0_1

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その他リンク： http://hdl.handle.net/10191/17679

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.5575/geosoc.100.368

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

添付ファイル： 45_Matsuoka_1993d_NOM_J.pdf

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：日本古生物学会  

Living radiolarians were collected from the surface water around the Sesoko Island by using a plankton net. The fauna is composed of more than 30 species. The dominant species are Didymocyrtis tetrathalamus tetrathalamus, Euchitonia elegans, Tetrapyle octacantha, Pterocanium praetextum praetextum, Pterocorys zancleus. This paper documents the result of light microscopic observation of the following nine species; Dictyocoryne profunda, Dictyocoryne truncatum, Euchitonia elegans, Lophophaena hispida, Eucyrtidium hexastichum, Pterocanium praetextum praetextum, Carpocanistrum coronatum, Acanthodesmia vinculata, Zygocircus productus.

DOI： 10.14825/kaseki.54.0_1

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その他リンク： http://hdl.handle.net/10191/17678

記述言語：英語   掲載種別：研究論文（その他学術会議資料等）   出版者・発行元：College Station  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：日本古生物学会  

Light microscopic observation of discoidal Spumellarida and their symbionts reveals that species belonging to the Family Spongodiscidae, Dictyocoryne truncatum, Dictyocoryne profunda, Hymeniastrum euclidis, Spongaster tetras, and Spongodiscus sp., commonly possess reddish-brown symbiotic bacteria (<1.5μm in diameter). Euchitonia elegans of the Family Porodiscidae has both yellow symbiotic algae (5-8μm in diameter) and symbiotic bacteria. The number of symbionts and their distribution pattern in the host differ among species, suggesting that the observation of symbionts is useful in distinguishing species which have a morphologically similar shell. Laboratory-cultured radiolarian specimens move their symbiotic bacteria to the axopodia which are located near the light source, strongly suggesting that the symbiotic bacteria are photosynthetic organisms and that the host radiolarians transport them towards the light source to enhance their photosynthesis activity. Symbiotic algae and bacteria of E. elegans differ in their relationship with the host ; the former disappears while the latter remains within the host when the host becomes weakened or dies. This indicates that the symbiotic algae are ectosymbionts and that the symbiotic bacteria are endosymbionts.

DOI： 10.14825/kaseki.53.0_20

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その他リンク： http://hdl.handle.net/10191/17677

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

The Southern Chichibu terrane fringes the southern margin of the Jurassic-Early Cretaceous accretionary complex of southwest Japan. Two subterranes, the Togano subterrane in the north and Sambosan subterrane to the south, are recognized by examination of the common features of the terrane. They are juxtaposed throughout the terrane from western Kyushu to the Kanto Mountains a distance of over 1000 km. The geology of the Sakawa area, central Shikoku, is described in detail to show an example of the terrane. The geology around Tsukumi in eastern Kyushu and Okutama in the Kanto Mountains is introduced to emphasize the common features of this terrane.
The Togano subterrane is composed of predominantly Triassic-Jurassic chert-clastic sequences associated with subordinate Jurassic olistostromal sequences and Upper Jurassic-Lower Cretaceous limestone-bearing clastic sequences. The chert-clastic sequences show an upward-coarsening sequence which reflects landward drift of the sea floor from a pelagic realm towards a trench. The olistostromal sequence contains abundant upper Paleozoic blocks. This subterrane is characterized by a south-vergent imbricate structure and south-younging polarity of the chert-clastic sequences.
The Sambosan subterrane consists of mainly Upper Jurassic-Lower Cretaceous olistostromal sequences associated with Upper Jurassic-Lower Cretaceous limestone-bearing clastic sequences. The olistostromal sequence includes abundant Triassic-Jurassic chert blocks and Triassic limestone blocks accompanied by greenstones. The limestone-bearing clastic sequences of both subterranes are regarded as shelf or inner-trench slope sediments deposited on the chert-clastic and olistostromal sequences.
Two major stages of tectonic development are discriminated. The Togano subterrane was formed by successive offscrape-accretion mainly during the Middle to Late Jurassic. The Sambosan subterrane was constructed by collision-accretion of seamounts mainly during the Late Jurassic to Early Cretaceous. The difference in the tectonic processes is considered to relate to topography of subducting oceanic plate; an oceanic plate with an abyssal plain for the Togano subterrane and an oceanic plate with seamounts for the Sambosan subterrane.

DOI： 10.1016/0031-0182(92)90060-I

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記述言語：日本語   掲載種別：研究論文（その他学術会議資料等）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

The stages of skeletal growth of the radiolarian Dictyocoryne truncatum were observed using scanning electron and light microscopy. Four growth stages were recognized through comparison of laboratory-grown individuals with various sized skeletons which were collected by plankton tows near Barbados. Skeletal size is expressed as test height, which is the largest value among the three dimensions between a base line and arm apex of a trianglar skeleton. The early stage (stage 1), with a maximum height of less than approximately 120 mum, is a uniformly spongiose, triangular skeleton lacking arms and a patagium. The next stage (stage 2 ) is a triangular skeleton with slightly concave sides of ca. 120-200 mum size with three arms and a lace-like patagium. Further accretion of silica on the patagium conceals its lace-like structure, making a skeleton (stage 3: ca. 200-280 mum) with a more uniformly spongiose patagium. The mature stage (stage 4) with a maximum height more than ca. 280 mum is a triangular skeleton with convex sides, resulting from an outward growth of the patagium. Additional maturation produces an accretion of spongiose silica on the central part of the skeleton, forming a thickly biconvex skeleton in transverse section. One hundred and one individuals of D. truncatum were cultured in the laboratory at 28-degrees-C, 35 parts per thousand salinity and 165 muE/m2/s light intensity, with maximum and mean longevity of 37 and 6.4 days, respectively. The mean growth of 57 specimens which grew in the laboratory culture was 24.7 mum, with a maximum of 95 mum. The initial size of cultured specimens ranged from 103 to 325 mum, covering all of the four growth stages. Some specimens grew from one stage to the next stage changing skeletal morphology. The mean growth rate of four specimens which grew from stage 3 to 4 in laboratory culture was 5.4 mum/day (range 4.5-6.5 mum/day). Sporadic growth patterns exhibiting periods of rapid growth (15-20 mum per day) punctuated by intervals of little or no growth were observed in some cultured specimens. The sporadic growth may be related to a physiological rhythm of the organisms rather than environmental factors. The silica-depositing capacity is related largely to the vitality of the organisms. Discolored specimens and specimens with weakly extended axopodia showed no skeletal growth.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

The longevity and skeletal growth of Dictyocoryne truncatum, collected from surface waters near Barbados, were assessed in laboratory culture in relation to variations in temperature and salinity. The range of longevities for groups of organisms collected at different times, but maintained at 28-degrees-C and 35.0 parts per thousand salinity, exhibited a wide fluctuation (1-2 to 5-37 days). The amount of growth also showed a wide variation among the groups since it was generally proportional to the longevity. The causes of the variation in longevity and growth are not known, but we hypothesize that a combination of genetic variability and physical and biological factors intrinsic to the culture conditions produced the variability.
D. truncatum showed a narrow temperature range for skeletal growth with an optimum in our culture conditions at about 28-degrees-C. Temperatures over 32-degrees-C or under 21-degrees-C suppressed skeletal growth. D. truncatum has a much wider temperature tolerance for survival than for growth. Longevity at temperatures as low as 15-degrees-C was comparable to that at 28-degrees-C. This indicates that D. truncatum can endure periods of relatively low temperatures. This may have survival advantage by conferring resistance to lower temperatures at great depths in the water column or during intrusion of colder water masses into warmer surface water regimes, but we have presently no evidence of their reproductive capacity at these lower temperatures. These results are consistent with a theory that D. truncatum is largely a surface-dwelling species surviving optimally in warmer water that supports optimum skeletal growth and maturation. The tolerance of cooler water, however, may also reflect biological adaptations related to variations in habitat during the reproductive cycle. Mature organisms may sink and release reproductive swarmers at greater depths in a water column, judging from the observation that mature individuals in culture withdrew their axopodia prior to swarmer release and settled to the bottom of culture vessels. The low temperature tolerance may also permit survival of juvenile organisms until they ascend into more warm surface water strata.
Cultured D. truncatum has a wide growth and survival tolerance for variations in salinity. Mean growth and longevities were comparable at salinities of 27 parts per thousand and 35.0 parts per thousand. A broad tolerance for variations in salinity can enhance survival at locations where wide variations in salinity occur regularly as happens near Barbados where the surface water is diluted by river outflows. The low salinity tolerance is also consistent with the interpretation that D. truncatum dwells in near-surface water in low latitude, open ocean locations.

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

添付ファイル： 38_Matsuoka_1992f_NOM_J.pdf

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：地学団体研究会  

This paper is part of our serial works on Paleozoic-Mesozoic systems in the Takaharagawa district. Five geological units are discriminated in the study area, namely Daihugendake,Wasabidani, Takahara, Obadanigawa, and Akataki Formations, intectonostratigra phically descending order. The Daihugendake.Wasabidani and Takahara Formations belong to the Chichibu Terrane, while the Obadanigawa and Akataki Formations belong to the Shimanto Terrane. The Daihugendake Formation is composed of chert-clastic sequences of Middle Triassic-Late Jurassic age. The sequences form an imbricate structure. The Wasabidani Formation is Late Jurassic melange including Middle-Late Triassic limestone, greenstone and chert blocks. The Takahara Formation comprises melange of early - middle Early Cretaceous age containing chert, limestone and greenstone blocks and the upper part of the formation is characterized by a dominance of sandstones. The Obadanigawa Formation consists mainly of Albian-Cenomanian sandstone-rich clastic sequences associated subordinately with melange which contains various blocks derived from the Chichibu Terrane. The Akataki Formation is Turonian melange containing red chert, red mudstone and green-stone blocks. These units have been stacked up to form a pile nappe structure, showing a younging age polarity from the upper unit to the lower one. Their contacts are marked by thrust faults parallel to the general trend of the strata. A slight structural discordance, however, is partly recognized between the Chichibu and Shimanto Terranes. This paper points out two possible interpretations concerning the tectonic evolution of the Chichibu and Shimanto Terranes. One interpretation is that the geological units of the two terranes were formed through successive accretionary processes from Late Jurassic to Cretaceous time. The other is that the Chichibu and Shimanto terranes were formed independently and the former has been thrust over the latter at a later stage, forming a large scale nappe structure.

DOI： 10.15080/agcjchikyukagaku.46.3_185

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：INT SCIENCE SERVICES/BALABAN PUBLISHERS  

Micro-algae (c. 2.5 to 3.5 mum wide x3.8 to 4.5 mum long) occur abundantly within perialgal vacuoles in the intracapsular cytoplasm of the radiolarian Dictyocoryne truncatum, a triangular-shaped, spongiose skeletal radiolarian. The fine structure of the microalgae resembles that of yellow-brown pigmented symbionts observed in larger spongiose skeletal radiolaria of the spongodrymid type. The density of microalgae in a typical ultrathin section is c. 4/100 mum2. Bacteroids (0.2x0.5 mum) are present throughout the intracapsular cytoplasm. There is no evidence of a vacuolar membrane enclosing the bacteroids, but each is surrounded by an electron lucent zone. The central capsule of radiolaria contains the nucleus and cytoplasmic organelles and is bounded by a capsular wall. Previously, algae associated with radiolaria have been observed in the extracapsulum. The occurrence of intracapsular microalgae in D. truncatum is of interest since this indicates that the intracapsular cytoplasm, previously thought to be largely specialized for metabolism, storage of reserve substances and production of reproductive swarmers, can also be a site for host-algal interactions.

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

添付ファイル： 30_Matsuoka_1991a.pdf

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：日本古生物学会  

美濃帯南条山地のマンガンバンドから得られた前期ジュラ紀放散虫記載の第1報として, 表題のNassellaria3属(Minocapsaは新属)について, 以下の9新種(2新亜種を含む)を命名, 記載した。T. minoensis, T. (?) megaglobosa, T. (?) fera, S. plicata plicata, S. plicata semiplicata, S. elegans, S. biconsica, S. nanjoensis, M. cylindrica, M. globosa.このマンガンバンドから産出した放散虫群集は, わが国で設立されたジュラ紀化石帯のうちArchicapsa pachyderma帯上部の群集に類似する。また, この群集は, 北アメリカのオレゴン州中東部のトアルシアン階下部から産出する放散虫群集に比較される。

DOI： 10.14825/prpsj1951.1991.161_720

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その他リンク： https://jlc.jst.go.jp/DN/JALC/10014400925?from=CiNii

記述言語：英語   掲載種別：研究論文（その他学術会議資料等）   出版者・発行元：Publication of IGCP Project 224  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER GEOLOGICAL INST  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：NATURE PUBLISHING GROUP  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.5575/geosoc.96.239

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記述言語：日本語   出版者・発行元：日本地質学会  

DOI： 10.14863/geosocabst.1990.0_394

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：日本古生物学会  

Radiolarian fossils have been newly discovered from the uppermost part (Koyamada Formation) of the Somanakamura Group in the eastern marginal zone of the Abukuma Mountains, northeast Japan. The radiolarian fauna contains Pseudodictyomitra sp. cf. P. carpatica (Lozyniak), Sethocapsa sp. cf. S. kaminogoensis Aita, Hemicryptocapsa capita Tan Sin Hok, and so on. This association indicates an early Early Cretaceous age. The age assignment is consistent with that by ammonites (Berriasian).

DOI： 10.14825/kaseki.46.0_11

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その他リンク： http://hdl.handle.net/10191/17676

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：地学団体研究会  

Lithologic characters and radiolarian fossil evidence suggest that the Miyoshino district is occupied by Cretaceous strata belonging to the Shimanto Belt, except for the B Formation (Chichibu Belt) which is distributed in the uppermost part of tectonic piles as a nappe. The formations (tentatively nominated) in this district and their ages are as follows. Akataki Formation; Turonian〜 Takahara Formation; Jurassic-Cretaceous Makio Formation; Coniacian-Santonian〜 Miyoshino Formation; Late Albian-Cenomanian〜 Heibara Formation; Jurassic-Cretaceous The strata of the Shimanto Belt are widely distributed in the central area of the Kii Mountains including the study district. It is possible that the Shimanto Belt is in fault contact with the Sambagawa Belt, lacking the Chichibu Belt.

DOI： 10.15080/agcjchikyukagaku.43.3_119

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.5575/geosoc.94.583

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.15080/agcjchikyukagaku.42.2_104

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：日本古生物学会  

Fossil evidence of radiolarians reveals the age of the Shiriya Group (olistostrome facies) in the North Kitakami Belt (s. l.). Some olistoliths of chert are Early Jurassic and Middle-Late Jurassic in age. A tuffaceous mudstone sample contains the following radiolarians; Pantanellium lanceola (Parona), Parvicingula boesii (Parona), Pseudodictyomitra sp. cf. P. carpatica (Lozyniak) and others. The association of the radiolarians indicates that the examined sample is late Tithonian-earliest Cretaceous in age. It is not clear whether the tuffaceous mudstone represents a matrix of the olistostrome or it is also an olistolith itself within the olistostrome. It is certain, however, that the formation of the olistostrome continued during late Tithonian-earliest Cretaceous or later in the North Kitakami Belt (s. l.).

DOI： 10.14825/kaseki.42.0_7

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：日本古生物学会  

Nine radiolarian assemblage-zones (A-z) are recognized in the Jurassic and the lowermost Cretaceous sequences of Japan, namely, in ascending order, the Parahsuum simplum A-z (early Early Jurassic); the Parahsuum sp. D A-z (middle Early Jurassic), the Hsuum sp. B A-z (late Early Jurassic), the Unuma echinatus A-z (Bajocian-early Bathonian), the Guexella nudata A-z (late Bathonian-Callovian), the Gongylothorax sakawaensis-Stichocapsa naradaniensis A-z (Oxfordian), the Tricolocapsa sp. O A-z (Kimmeridgian), the Pseudodictyomitra primitiva-Pseudodictyomitra sp. A A-z (Tithonian) and the Pseudodictyomitra cf. carpatica A-z (Berriasian). In this radiolarian biostratigraphic framework, the stratigraphic range of four multi-segmented nassellarian genera (Parahsuum, Hsuum, Archaeodictyomitra and Pseudodictyomitra) is investigated. Hsuum with discontinuous costae and Parahsuum disappeared in the P. primitiva-P. sp. A A-z and in the T. sp. O A-z, respectively. A certain group of Archaeodictyomitra, which occurs abundantly in the Lower Cretaceous, first appeared in the T. sp. O A-z. Pseudodictyomitra made the first appearance at the base of the P. primitiva-P. sp. A A-z. Judging from the stratigraphic range of the above-mentioned four genera, it is pointed out that a remarkable faunal change took place in the T. sp. O A-z and/or the P. primitiva-P. sp. A A-z, which are assigned to Kimmeridgian-Tithonian in age.

DOI： 10.14825/kaseki.40.0_1

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

添付ファイル： 16_Matsuoka_1986d_NOM_J.pdf

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

添付ファイル： 17_Matsuoka_1986e_NOM_J.pdf

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記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：大阪市立大学  

添付ファイル： 14_Matsuoka_1986b.pdf

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.5575/geosoc.91.411

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記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：大阪市立大学  

添付ファイル： 12_Matsuoka_Yao_1985b.pdf

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：日本地質学会  

高知県西部の秩父累帯南帯には，チャートと粗粒砕屑岩とのくりかえしで特徴づけられる地層が広く分布する．このくりかえしは，下位から層状珪質粘土岩層，チャート層，珪質泥岩層，粗粒砕屑岩層からなる層序ユニット（トリアス紀中世からジュラ紀中世ないし新世）が北方上位・北傾斜で構造的にくりかえして重なり覆瓦状構造を呈するためにみられるものである．この層序ユニットを斗賀野層群として再定義した．詳細な放散虫生層序学的検討の結果，同層群のチャート層の上限の年代や珪質泥岩層・粗粒砕屑岩層の年代が北から南に向かって若くなるという年代的極性をもつことが明らかになった．斗賀野層群の基本的層序にみられる岩相の垂直変化は，堆積場が遠洋域から陸源物質の供給される場に移化したことを示すと解釈される．上述した斗賀野層群の性質は，弧―海溝系で提唱されている付加体モデルと矛盾しない．In the present area, Mesozoic strata are widely distributed. Based on lithology and fossil contents, they are divided into five Groups or Formations, namely Togano Group (Middle Triassic-Late Jurassic), Naradani Formation (Late Jurassic), Torinosu Group (late Late Jurassic-? Early Cretaceous), Yamanokami Formation (Early Cretaceous) and Bandagamori Formation (Late Jurassic-). As the first step of the geologic study in this area, the Togano Group is described and discussed. The Togano Group consists mainly of chert and coarse elastics (sandstone, sandstone-rich alternation of sandstone and mudstone, rarely conglomerate) associated with mudstone, siliceous mudstone, bedded siliceous claystone, acidic tuff and olistostrome, and is characterized by apparently alternate occurrence of chert and coarse clastics. The above rock types are grouped into four lithostratigraphic members, namely chert layer, coarse clastic layer, bedded siliceous claystone layer and siliceous mudstone layer. The alternate occurrence of chert and coarse elastics is due to repetition of stratigraphic unit (Middle Triassic-Middle or Late Jurassic) composed, in ascending order, of (1) bedded siliceous claystone layer, (2) chert layer, (3) siliceous mudstone layer and (4) coarse elastics layer. The stratigraphic units are tectonically piled up to form north dipping imbricate structure. As the result of detailed radiolarian biostratigraphic study, it is revealed that the age of the top of the chert layer (2), and the age of the siliceous mudstone layer (3) and the coarse clastics layer (4) become systematically younger from the northern stratigraphic units to the southern ones. Lithological facies change of the stratigraphic units of the Togano Group indicates that sedimentary environment changed from pelagic through hemipelagic to terregenous environment. The above-mentioned features of the Togano Group are consistent with the accretion model proposed in arc-trench system.

DOI： 10.5575/geosoc.90.455

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その他リンク： http://hdl.handle.net/10191/6260

記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：大阪市立大学  

添付ファイル： 09_Matsuoka_1984a.pdf

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.5575/geosoc.89.407

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記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）  

添付ファイル： 07_Matsuoka_1983a.pdf

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

添付ファイル： 05_松岡_1982b_NOM.pdf

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

添付ファイル： 06_八尾ほか_1982c_NOM.pdf

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記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：大阪市立大学  

添付ファイル： 04_Matsuoka_1982a.pdf

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記述言語：英語   出版者・発行元：国立科学博物館  

There are two lithologic units in strata in the central area of the Kii Mountains. One of them belongs to the Chichibu Belt and is subdivided into three formations : B, C and D in ascending order. The other unit of Cretaceous in age is a member of the Shimanto Belt. Besides them, there is O Formation exclusively found between the two units. The B Formation is composed of mudstone, chert and large limestone bodies accompanied with greenstones. The limestone bodies contain Late Triassic conodonts, and the mudstone rarely yields Jurassic radiolarians. The C Formation is made up of thick chert beds, intercalated with layers of mudstone, sandstone, acidic tuff, limestone and greenstones. Late Paleozoic and Mesozoic fossils are found sporadically in this formation. The D Formation is characterized by conglomerate containing abundant pebbles and cobbles of limestone. The O Formation consists largely of mudstone with subordinate sandstone. The constituent of the formation is a chaotic sediment involving blocks rich in dimensional and lithological diversity, yielding fossils of various ages. The Cretaceous strata in the Shimanto Belt comprise sand- and mud-abundant portions. In each mud-abundant portion are a few horizons involving greenstones, chert and acidic tuff. Among them, the siliceous parts yield Cretaceous radiolarians. Such juxtaposition of rocks of different ages as shown in the B and C formations is interpreted as the product of tectonic and/or sedimentary rearrangement. From the lithofacies and fossil contents, the formation of the chaotic part of the O Formation was due to mingling during and after sedimentary processes. The B, C and D formations, gently dipping north to northeast, overlie structurally the Cretaceous strata and partly the O Formation. The Cretaceous strata dipping 40°to 60°northwest show recurrence of the muddy portions. The B or C formation and the Cretaceous strata or the O Formation are in fault contact with each other. This fault having gentle dip corresponds to the Butsuzo Tectonic Line. The Cretaceous strata in the Shimanto Belt may be in fault contact directly with the Sanbagawa metamorphics in western half of the area without the B, C and D formations or the Chichibu Belt.

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記述言語：英語  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語

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記述言語：日本語 著書種別：一般書・啓蒙書

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記述言語：日本語 著書種別：一般書・啓蒙書

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記述言語：日本語 著書種別：学術書

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記述言語：英語 著書種別：学術書

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記述言語：日本語 著書種別：学術書

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記述言語：日本語 著書種別：学術書

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記述言語：日本語 著書種別：事典・辞書

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記述言語：日本語 著書種別：事典・辞書

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記述言語：日本語 著書種別：学術書

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記述言語：日本語 著書種別：学術書

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記述言語：日本語  

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記述言語：日本語  

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記述言語：日本語  

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記述言語：英語   出版者・発行元：日本花粉学会  

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記述言語：日本語   掲載種別：記事・総説・解説・論説等（その他）   出版者・発行元：大阪市立自然史博物館友の会  

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記述言語：英語   掲載種別：記事・総説・解説・論説等（その他）   出版者・発行元：Niigata University  

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記述言語：日本語   掲載種別：記事・総説・解説・論説等（その他）   出版者・発行元：新潟県高等学校教育会理科部会  

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記述言語：日本語  

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記述言語：日本語   出版者・発行元：日本古生物学会  

DOI： 10.14825/kaseki.79.0_1

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記述言語：日本語   出版者・発行元：日本古生物学会  

DOI： 10.14825/kaseki.71.0_19

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その他リンク： http://hdl.handle.net/10191/17680

記述言語：日本語  

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記述言語：日本語   掲載種別：講演資料等（セミナー，チュートリアル，講習，講義他）  

2001年11月10日放送

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記述言語：英語   出版者・発行元：The Geological Society of Japan  

The Malampaya Sound Group is predominantly composed of chert (Liminangcong Formation), clastics (Guinlo Formation) and scattered limestone units that characterize the North Palawan Block (Zamoras and Matsuoka, 2001). In the Calamian Islands (grouping Busuanga, Coron, Culion and other smaller islands) the Liminangcong Formation is represented by Permian to Late Jurassic chert; the Guinlo Formation is represented by Middle-Late Jurassic to Early Cretaceous clastics.<BR>The common succession from chert to clastics with generally conformable contact is thus referred to as a chertclastic sequence. In Busuanga Island, linear topographic patterns reveal the parallel distribution of chert-clastic sequences dipping generally NW in the west, and NE in the central and eastern portions. This chert-clastic repetition indicates an imbricate structure typical to offscrape accretion complexes.

DOI： 10.5575/geosoc.107.XI

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記述言語：日本語  

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記述言語：日本語   出版者・発行元：日本地質学会  

秩父累帯の主要部は, ジュラ紀の付加体からなる. 付加体に含まれるチャートや石灰岩などの海洋性物質について, その堆積年代や含まれる化石の古生物地理学上の特徴を明らかにすることにより,秩父累帯の形成モデルに制約を与えることができる. また, 地質構造の特徴は, 付加体形成から現在にいたるまでのプロセスを反映している, 秩父累帯を構成する主要なユニットについて, 露頭のようすや山塊の表情を紹介する. 斗賀野ユニットと三宝山ユニットは南部秩父帯に, 柏木ユニット, 住居附ユニットおよび沢谷ユニットは北部秩父帯にそれぞれ属する.

DOI： 10.5575/geosoc.104.XXI

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記述言語：日本語  

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開催年月日： 2022年9月

記述言語：英語   会議種別：口頭発表（基調）  

開催地：Ljubljana   国名：スロベニア共和国  

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開催年月日： 2022年9月

記述言語：英語   会議種別：ポスター発表  

開催地：Ljubljana   国名：スロベニア共和国  

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開催年月日： 2022年8月 - 2022年9月

記述言語：英語   会議種別：口頭発表（一般）  

開催地：Budapest   国名：ハンガリー共和国  

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開催年月日： 2022年8月 - 2022年9月

記述言語：英語   会議種別：口頭発表（一般）  

開催地：Budapest   国名：ハンガリー共和国  

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開催年月日： 2022年8月

記述言語：英語   会議種別：口頭発表（一般）  

開催地：ワルシャワ   国名：ポーランド共和国  

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開催年月日： 2022年7月

記述言語：日本語   会議種別：口頭発表（一般）  

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開催年月日： 2022年7月

記述言語：日本語   会議種別：口頭発表（一般）  

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開催年月日： 2022年7月

記述言語：日本語   会議種別：口頭発表（一般）  

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開催年月日： 2022年7月

記述言語：日本語   会議種別：口頭発表（一般）  

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開催年月日： 2022年7月

記述言語：日本語   会議種別：口頭発表（一般）  

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開催年月日： 2021年11月

記述言語：日本語   会議種別：口頭発表（一般）  

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