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Ordovician chitinozoan diversification events in China

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Science China Earth Sciences 2004年第10期47卷 874-879页

作者： WANG Xiaofeng CHEN Xiaohong Center for Stratigraphy and palaeontology CGS Yichang 443003 China Center for Stratigraphy and Palaeontology CGS Yichang 443003 China

Correlative study of the Ordovician chitinozoan biostratigraphy in China with grap- tolite and conodont biozones, and comprehensive analysis of the sequence- and event-strati- graphic indicated that 17 chitinozoan zones and 5 main chitinozoan diversification events subsequently occurring could be recognized in the Ordovician System of China. The 5 events comprise: event 1 — appearance of the earliest Ordovician chitinozoans, event 2 —appearance of C. symmetrica, event 3 —juvenile radiation of chitinozoans, event 4 —appearance of chitinozoans with high diversity, and event 5 —development of chitinozoans of deep-water facies. The age and feature of each event and its relation with the sea-level change and other geological event are discussed.

关键词： chitinozoan, Ordovician, diversification event.

Ovarian follicles shed new light on dinosaur reproduction during the transition towards birds

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National Science Review 2014年第1期1卷 15-17页

作者： Jingmai K.O'Connor Yan Wang Zhonghe Zhou Xiaoting Zheng Xiaoli Wang Institute of Vertebrate palaeontology and Paleoanthropology Chinese Academy of Sciences Institute of Geology and palaeontology Linyi University Shandong Tianyu Museum of Nature

The reproductive systems of living archosaurs,crocodilians and birds are very diferent;the derived features present in birds are inferred to have evolved within the derived archosaur group,Dinosauria,which includes Aves(the common ancestor of Archaeopteryx+living birds)as a member of the derived theropod clade,*** to Aves,crocodilians have two ovaries,prolonged folliculogenesis(maturation

关键词： body Ovarian follicles shed new light on dinosaur reproduction during the transition towards birds

Evolution of Carbon Isotope Composition in Potential Global Stratotype Section and Point at Luoyixi, South China, for the Base of the Unnamed Global Seventh Stage of Cambrian System

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Journal of China University of Geosciences 2008年第1期19卷 9-22页

作者：左景勋彭善池朱学剑祁玉平林焕令杨显峰 Nanjing Institute of Geology and palaeontology Chinese Academy of Sciences Nanjing 210008 China Henan Institute of Geological Survey Zhengzhou 450001 China State Key Laboratory of palaeontology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences

This work deals with the evolution of carbon isotope composition in the Luoyixi （罗依溪） Section, a candidate of the Global Standard Stratotype-section and Point （GSSP）, defining the base of the as-yet-undefined seventh stage of Cambrian System at the first appearance of the cosmopolitan agnostoid Lejopyge iaevigata. This level is favored in a vote of International Subcommission on Cambrian Stratigraphy （ISCS） as the biohorizon for defining the base of a global stage. Two hundred and sixty-four samples for carbon and oxygen isotope analysis have been collected from the carbonate successions at an interval of 0.25 to 0.5 m in this section. Results of the carbon isotope data exhibit a remarkable disciplinarian trend. The pattern of the carbon isotope evolution is gently undulant with a relatively long period during the underlying Drumian Stage, and then the values of δ13C fluctuate sharply with a short period in provisional seventh stage. The onset of sharp fluctuation in the δ13C values begins at the proposed GSSP level, defining the base of the global seventh stage, where δ13C values change from a gentle trend to a sharp trend. Distinct covariant-relationships among δ13C,δ18O, and sea level fluctuations suggest that a warming change in paleoclimate took place during the early global seventh stage, which led to a positive shift in δ13C values.

关键词： carbon isotope composition global seventh stage of Cambrian System Luoyixi Section northwestern Hunan (湖南).

Homo erectus pekinensis's age and environment——with discussion on the relationship among Homo erectus from Beijing,Nanjing and Chenjiawo

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Science China Earth Sciences 2004年第1期47卷 68-77页

作者： LIU Jinling WANG Weiming Nanjing Institute of Geology and palaeontology Chinese Academy of Sciences Nanjing 210008 China Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China

This paper inspects the relationship between Homo erectus from Beijing, Nanjing and Chenjiawo on the viewpoint of environmental variations. Pieces of evidence show that Nanjing and Chenjiawo Homo erectus lived in glacial age at the Marine Oxygen Isotope Stage (MIS) 16, while Homo erectus pekinensis in major interglacial age at MlSs 15-13. It is also recovered that the cave deposits in Tangshan, Nanjing, and Zhoukoudian, Beijing, as well as the deposits at the Homo erectus site in Chenjiawo, have undergone some similar development process. All of them originated from early-middle Middle Pleistocene, and have gone through the test of the major glacial age at MIS 16 and the major interglacial period at the paleosol stage S5. At the same time, they were also closely connected with some environment events, such as the uplift of the Qinghai-Xizang Plateau, the formation of glaciations and the loess accumulations.

关键词： Homo erectus from Beijing, Nanjing and Chenjiawo, climate and environment, comprehensive comparisons.

Biostratigraphical significance of the Devonian Sinoleperditiini(Ostracoda)

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Science China Earth Sciences 2005年第10期48卷 1666-1671页

作者： WANG Shangqi PENG Jinlan Nanjing Institute of Geology and palaeontology Chinese Academy of Sciences Nanjing 210008 China Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China

The Tribe Sinoleperditiini (Ostracoda), which is mainly distributed in South China and its adjacent areas, is a single natural group of the Leperditiidae, characterized by the development of a trailing chevron muscle scar. This tribe is known only from the Devonian and ranges through most of the Devonian. The evolutionary trends within the Sinoleperditiini have been well documented and are exemplified by changes in the trailing chevron muscle scar. The main evolutionary change is a tendency of the trailing chevron muscle scar to extend ventrally through time, as demonstrated by the increasing ratio (th/ah) of the vertical height of the trailing chevron muscle scar (th) to that of the adductor muscle scar (ah). The recent discovery of a sinoleperditiine assemblage (th/ah values available) in the middle-upper Lower Emsian Shanglun Formation allows to propose a sinoleperditiine biostratigraphical sequence for the Devonian. This sequence contains 11 assemblages (th/ah value available for each assemblage), which cover all the 7 Devonian stages and some substages. This sequence is particularly useful for correlating and dating Devonian rocks in the littoral clastic, lagoonal and restricted or semirestricted car-bonate platform facies where these ostracodes are most abundant and other fossils are un-common.

关键词： Sinoleperditiini biostratigraphical sequence, Devonian, South China.

A Different Opinion on the Geological Age of the Longzhaogou and Jixi Groups of Eastern Heilongjiang, China

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Acta Geologica Sinica(English Edition) 1992年第2期66卷 209-218,223页

作者： Sha Jingeng Nanjing Institute of Geology and palaeontology, Academia Sinica, Nanjing, Jiangsu Nanjing Institute of Geology and palaeontology Academia Sinica Nanjing Jiangsu

The age of the Longzhaogou and Jixi Groups of coal measures in eastern Heilongjiang were previouslyconsidered to be Jurassic or mainly Jurassic. But there occur Middle Barremian-Early Albian Aucellina(bivalvia) fossils in the Upper Yunshan Formation of the Longzhaogou Group and the Lower Chengzihe For-mation of the Jixi Group, and the Qihulin Formation of the Longzhaogou Group yields Early Cretaceousbivalve and ammonite fossils. Consequently, the geological ages of the two groups are mainly, or even all, Ear-ly Cretaceous.

关键词： A Different Opinion on the Geological Age of the Longzhaogou and Jixi Groups of Eastern Heilongjiang China

Evolutionary Trends of the Genus Ancyrogondolella(Conodonta)and Related Taxa in the Norian(Late Triassic)

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Journal of Earth Science 2021年第3期32卷 700-708页

作者： Viktor Karadi Department of palaeontology Eotvos Lorand UniversityBudapest 1117Hungary

The Norian represents the longest stage of the Triassic,nevertheless,its precise subdivision is an unresolved *** might be useful in the establishment of an accurate biozonation to avoid common scientific *** the Norian evolutionary trends and morphological changes of the Ancyrogondolella lineage(genus Ancyrogondolella and descendant genera Epigondolella,Orchardella and Mockina)is of key importance in this *** forward shifting of the pit and the posterior prolongation of the keel and the carina characterize the main trend that corresponds to the faunal turnover around the Lacian-Alaunian transition.A gradual decrease in overall element width and length can be observed from that time on,which couples with a decrease in the length of the free blade and an increase in the height of the anterior platform *** presence of secondary carinae is characteristic for the mid-Lacian 1 to Alaunian 1,but their development shows no trends and has no taxonomic *** specimens of the Lacian generally have an arched lower profile,whereas in the Alaunian and Sevatian the lower profile is dominantly stepped or *** thorough documentation of the Tethyan assemblages is needed for any detailed taxonomic and paleobiogeographic comparisons with other regions.

关键词： conodonts evolution Ancyrogondolella Late Triassic Norian Lacian Alaunian Sevatian

Distribution patterns of the Jurassic ostreids (Bivalvia) from Tanggula of China

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Science China Earth Sciences 2001年第S1期44卷 112-120页

作者：沙金庚 Nanjing Institute of Geology and palaeontology Chinese Academy of Sciences Nanjing China

Distribution of the Jurassic ostreids (Bivalvia) from Tanggula area of China includes three patterns, which are (1) Tethys: containing Liostrea birmanica and Eligmus rollandi, (2) western Europe and northern Tethys: consisting of Gryphaea (Bilobissa) bilobata; and (3) Global: composed of Actinostreon gregareum and Nanogyra nana. However, they are all limited between palaeolatidudes 60℃South and North. Actinostreon gregareum originated in the Sinemurian of northern Chile and it entered Kenya and Madagascar in the Toarcian, but there is no reliable Si-nemurian-Toarcian A gregareum fossil record in continental margins between Chile and Kenya and Madagascar. Such distribution patterns and dispersal processes have demonstrated that (1) during the Jurassic all seas and oceans were connected to each other; (2) the Tethys and the western European epicontinental seas did produce some endemic taxa; (3) the distribution of these ostreids was most likely controlled by latitudes and creature ecology; and (4) A, gregareum underwent a trans-Pacific dispersal from east to west.

关键词： Tanggula Jurassic ostreids distribution patterns.

Chronostratigraphic Subdivision and Correlation of the Permian in China

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Acta Geologica Sinica(English Edition) 1999年第2期73卷 127-138页

作者： JIN Yugan SHANG Qinghau WANG Xiangdong WANG Yue SHENG Jinzhang Nanjing Institute of Geology & palaeontology Chinese Academy of Sciences Nanjing 210008

Since the principle of multiple stratigraphic classification has been widely accepted by Chinese stratigraphers, various new Permian chronostratigraphic units have been proposed in China, and they need to be redefined. The establishment of a new global chronostratigraphic scheme of the Permian, compilation of Permian lithostratigraphic units and updating of Permian biostratigraphic sequences of China makes it possible to present a revised regional chronostratigraphic succession for the Permian System in China. This succession consists of three series and eight stages. The Chuanshanian Series includes two stages, the Zisongian and the Longlinian; the Yanghsinian (Yangxinian) Series is subdivided into the Chihsian (Qixiaan) and the Maokouan Subseries, of which the former comprises the Luodianian and the Xiangboan Stage, and the latter the Kufengian (Gufengian) and the Lengwuan Stage; the Lopingian (Lepingian) Series includes the Wuchiapingian (Wujiapingian) and the Changhsingian (Changxingian) Stage.

关键词： Chronostratigraphy Permian Chuanshanian Yanghsinian Lopingian China