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Yangtzedonta and the early evolution of shelled molluscs

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chinese Science Bulletin 2001年第24期46卷 2103-2106页

作者： QIAN Yinanjing institute of geology and palaeontology, chinese academy of sciences, nanjing 210008, china nanjing institute of geology and palaeontology Chinese Academy of Sciences Nanjing China

The holotype of Yangtzedonta Yu, 1985 and its type species, Y. primitiva Yu, 1985, is an incomplete specimen of Xianfengella prima He et Yang, 1982. Therefore, based on the principle of priority, the names Yangtzedonta and Y. primitiva Yu (1985) should be abandoned. The fact that ventral valve of Xianfengella is bilaterally symmetrical indicates that they are not the left valve of a bivalved mollusc, as originally proposed by Yu. At present, the oldest certain bivalve is Xianfengoconcha elliptica zhang, which occurs in the Early Cambrian Qiongzhusi Stage in china. The oldest known rostroconch is Heraultipegma yunnanensis He et Yang, which first occurs in the third small shelly fossil assemblage zone of the Early Cambrian Meishucunian Stage. The oldest known monoplacophoran, Maikhanella pristinis (Jiang), first occurs in the first small shelly fossil assemblage zone (Meishucunian Stage). Evidence derived from analyses of shell morphology, mode of growth, histology, and stratigraphic occurrence suggests

关键词： Yangtzedonta bivalves Xianfengella brachiopods enig- matic fossil.

Kalligrammatid Lacewings from the Upper Jurassic Daohugou Formation in Inner Mongolia, china

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Acta Geologica Sinica(English Edition) 2003年第2期77卷 141-147页

作者： zhang junfengnanjing institute of geology and palaeontology, chinese academy of sciences, nanjing, Jiangsu 210008, E-mail: jfzhang@*** chinese Acad Sci Nanjing Inst Geol & Palaeontol Nanjing 210008 Jiangsu Peoples R China

A new species, referable to a new genus, is erected, and named the Sinokalligramma jurassicum gen. et sp. nov. It is the second finding of kalligrammatids in the Daohugou Formation. The origin and migration of the family Kalligrammatidae are discussed. The geological age and stratigraphic correlation of the Daohugou and Karabastau Formations are briefly reviewed and reassessed.

关键词： kalligrammatid lacewings new taxa age origin and migration Jurassic Inner Mongolia china

Principal aspects of the Ordovician biotic radiation

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Science china Earth sciences 2010年第3期53卷 382-394页

作者： zhang YuanDong,ZHAN RenBin,FAN JunXuan,CHENG JunFeng & LIU Xiao LPS, nanjing institute of geology and palaeontology, chinese academy of sciences, nanjing 210008, china 1. LPS Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China

The Ordovician radiation is among the major bioevents in earth history that have drawn great attention from geologists all over the world, and there have been hundreds of publications treating various aspects of this radiation. The study of the event involves a broad spectrum of research fields and concerns many scientific questions. Many opinions and hypotheses have been proposed on the triggering and controlling factors of the radiation. Herein the authors critically review the study of the Ordovician radiation and dissect four principal aspects by synthesizing the studies over the past years: (1) relationships of the radiation to fossil clades, ecotypes, and environments, such as water depth, latitude, and climate; (2) the ecological structure and food webs of Ordovician marine organisms; (3) fossil records and true biodiversities; and (4) likely triggering and controlling factors of the Ordovician radiation. The authors also recommend approaches to furthering studies of these aspects.

关键词： Ordovician biotic radiation guild food web fossil record mechanism

Sedimentary environment of the Dajin conglomerate in Tibet, age of foraminiferan assemblages and their tectonic significance

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Progress in Natural Science:Materials International 2005年第11期15卷 1014-1020页

作者： YAN Zhen, FANG Aimin, PAN Yusheng, LI Jiliang, LIU Xiaohan, YU Liangjun and zhang Binggao (Laboratory of Lithosphere Tectonic Evolution, institute of geology and Geophysics, chinese academy of sciences, Beijing 100029, china institute of Tibet Plateau Research, chinese academy of sciences, Beijing 100029, china nanjing institute of Paleontology, chinese academy of sciences, nanjing 210008, china) Laboratory of Lithosphere Tectonic Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China. institute of Tibet Plateau Research Chinese Academy of Sciences Beijing 100029 China. nanjing institute of Paleontology Chinese Academy of Sciences Nanjing 210008 China

The Dajin conglomerate, which is one of the most important sedimentary successions of the Xigaze forearc basin in Tibet, china, consists of deep-shallow marine tuffaceous turbidites and clastic rocks bearing Nummulites, Assilina, Alveolina and Lock-hartia . These fossils are very similar to the foraminiferan in the Jialazi and Maila conglomerates, and those in Gangba and Dingri areas. They developed in the Eocene. By analyzing the spatial variation of Eocene sedimentary environments of Tibet Plateau and the foraminiferan in the Dajin conglomerate, we found that Eocene sedimentation should take place on both sides of the Yarlung Tsangpo suture, and the late Eocene tectonic uplifting should make the forearc basin expose out of the sea level and begin to receive nonmarine deposits.

关键词： Dajin conglomerate marine deposits Eocene foraminiferan Yarlang Tsangpo sutnre.

Two new species of Vestrogothia (Phosphatocopina, Crustacea) of Orsten-type preservation from the Upper Cambrian in western Hunan, South china

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Science china Earth sciences 2009年第6期52卷 784-796页

作者： zhang HuaQiao1,2 & DONG XiPing1,2 1 School of Earth and Space sciences,Peking University,Beijing 100871,china 2 State Key Laboratory of Palaeobiology and Stratigraphy,nanjing institute of geology and palaeontology,chinese academy of sciences,nanjing 210008,china School of Earth and Space sciences Peking University Beijing 100871 China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China

Although fossils of Orsten-type preservation represented by Skaracarida and Phosphatocopina were first reported from the Middle and Upper Cambrian in western Hunan, South china in 2005, diversified phosphatocopine species have never been appropriately described and elucidated in terms of their evolutionary relationships. Here, we described two new species of Phosphatocopina, Vestrogothia anterispinata sp. nov. and V. bispinata sp. nov. The evolutionary relationship among all the valid species of Phosphatocopina is discussed and the phylogeny of Phosphatocopina is reestablished using cladistic analysis. Accordingly, phosphatocopines primitively evolved along two lineages: one evolved towards the emergence of lobes; the other evolved towards the emergence of dorsal spines. Respectively, lobes originated independently three times, and dorsal spines originated only once. With regard to the dorsal rims, interdorsum originated first, whereas dorsal furrow originated independently twice on the basis of interdorsum. Probably Hesslandona may represent a polyphyletic group, whereas Vestrogothia a monophyletic group.

关键词： fossils of Orsten-type preservation Vestrogothia Phosphatocopina Crustacea evolution phylogeny Cambrian Hunan

A high-resolution late Pleistocene record of pollen vegetation and climate change from Jingning, NW china

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Science china Earth sciences 2006年第2期49卷 154-162页

作者： LI Chunhai12, TANG Lingyu1, FENG Zhaodong3,4, zhang Hucai2, WANG Weiguo3 & AN Chenbang3 1. nanjing institute of geology and palaeontology, chinese academy of sciences, nanjing 210008, china 2. Nanjng institute of Geography and Limnology, chinese academy of sciences, nanjing 210008, china 3. Environment and Resources College, Lanzhou University, Lanzhou 730000, china 4. Beijing Normal University, Beijing 100875, china 1. nanjing institute of geology and palaeontology Chinese Academy of Sciences Nanjing 210008 China 2. Nanjng institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China 3. Environment and Resources College Lanzhou University Lanzhou 730000 China 4. Beijing Normal University Beijing 100875 China

With the support of 18 AMS-14C data, a high-resolution pollen record from the Suancigou section at Jingning, Gansu Province was established. Our results showed that the vegetation ex-perienced a series of changes characterized by the alternative growth and decline of forest and steppe components during the period from 44.2 to 11 ka B.P. in the Jingning area. Over the period of 44―29 ka B.P. (MIS3), coniferous forests were flourishing, indicating a humid climate with the tem-perature being lower than that of the present. Since 23 ka B.P., the vegetation was dominated by steppe-desert steppe under a cold and dry condition, and entered the Last Glacial Maximum domi-nated by desert steppe. Several periods of the marked decrease in the arborous pollen content in Suancigou well corresponded to the North Atlantic Heinrich events, especially to Heinrich event 3, further supporting that the Heinrich events were well reflected by the pollen record in the Loess Pla-teau as well.

关键词： Western Loess Plateau, pollen record, climatic change, late Pleistocene.

Principles and methods of quantitative analysis on b-axis disorder in 2 : 1 dioctahedral phyllosilicate

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chinese Science Bulletin 1997年第22期42卷 1908-1912页

作者： WANG Ling and zhang Zhenyu1. Changsha institute of Geotectonics, chinese academy of sciences, Changsha 410013, china 2. institute of geology, chinese academy of sciences, Beijing 100029, china Changsha institute of Geotectonics Chinese Academy of Sciences Changsha China institute of geology Chinese Academy of Sciences Beijing China

IN XRD patterns of clay minerals, a phenomenon that strong peaks often have (00l) and(hkl) (k=3n) indices and show symmetric figures can be seen commonly, while a minorityof reflection peaks (hkl) (k≠3n) are comparat... 详细信息

关键词： b-axis disorder pyrophvllile 2 phyllosilicate clay minerals dioctahedral minerals orientating structure of hy-droxyls crystal structure analysis DTA-TG.

^(40)Ar/^(39)Ar dating of shear deformation of the Xianshuihe fault zone in west Sichuan and its tectonic significance

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Science china Earth sciences 2004年第9期47卷 794-803页

作者： zhang Yueqiao1, CHEN Wen2, 3 & YANG Nong1 1. institute of Geomechanics, chinese academy of Geological sciences, Beijing 100081, china 2. institute of geology, chinese academy of Geological sciences, Beijing 100037, china 3. institute of geology and Geophysics, chinese academy of sciences, Beijing 100029, china institute of Geomechanics Chinese Academy of Geological Sciences Beijing 100081 China institute of geology Chinese Academy of Geological Sciences Beijing 100037 China institute of geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

Based on field geological survey, structural measurements and classical Ar/Ar dating of mica, biotite and K-feldspar, we obtain cooling ages for Miocene left-lateral shear along the Xianshuihe fault zone. The results document two thermal events during the sinistral shear. The early event (12-10 Ma) corresponds to rapid cooling of the Zheduoshan granitic massif from above 700℃ to below 350℃. The late event (5-3.5 Ma) corresponds to cooling of granites intruded along the eastern side of the fault zone. These dating results provide important thermochronological constraint on the timing of late Cenozoic eastward extrusion of the Chuan-Dian Block in the SE Tibetan margin.

关键词： Xianshuihe fault zone, Zheduoshan granitic massif, sinistral shear deformation, 40Ar/39Ar dating, late Cenozoic.

A kind of coccoid dinoflagel-lates-like fossils gives a new explanation of source of dinosterane in the Early-Middle Cambrian

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chinese Science Bulletin 2001年第5期46卷 420-423,442页

作者： BIAN Lizeng, zhang Shuichang, zhang Baomin, MAO Shaozhi & YIN LeimingDepartment of Earth sciences, nanjing University, nanjing 210093,china Key Laboratory of Petroleum Geochemistry, china National Petroleum Corporation, Beijing 100083, china Research institute of Petroleum Exploration and Development, china National Petroleum Corporation, Beijing 100083, china china University of Geosciences, Beijing 100083, china nanjing institute of geology and palaeontology, chinese academy of sciences, nanjing 210008, china Department of Earth sciences Nanjing University Nanjing China Key Laboratory of Petroleum Geochemistry China National Petroleum Corporation Beijing China Research institute of Petroleum Exploration and Development China National Petroleum Corporation Beijing China china University of Geosciences Beijing China nanjing institute of geology and palaeontology Chinese Academy of Sciences Nanjing China

The coccoid fossils covered with thick gelatinous envelop containing several gametes are discovered in gyps and salt deposits of Cambrian, H4 well and chert bed of the base of Yuertus Formation (∈11) of Xiaoerbulake Section. The fossils are described and compared with coccoid dinoflagellates. These fossils may be a coccoid life-cycle stage (vegetative cyst) of coccoid dinoflagellates. If this identification is correct, the coccoid dinoflagellates-like fossils could give a reasonable explanation of the dinoflagellate-specific biomarkers from Cambrian, H4 well, Tarim Basin.

关键词： coccoid dinoflagellates-like fossils dinoflagellate-specific biomarkers Cambrian Tarim Basin.