检索结果-南通市图书馆

Discovery of Cathaysiodendron Lee from the Early Carboniferous of Jingyuan,Gansu,western China

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2004年第10期14卷 63-66页

作者： WANG Jun and WU Xiuyuan (nanjing Institute of geology and {2.,{3. academy of sciences,nanjing2.0008,China) chinese Acad Sci Nanjing Inst Geol & Palaeontol Nanjing 210008 Peoples R China

As one of the representative members of the Late Palaeozoic Cathaysian flora,Cathaysiodendron has been previously recorded from the Early Permian Taiyuan and Shanxi Formations in north *** species of Cathaysiodendron presented here are from the lower member of Chouniugou Formation of Ciyao,Jingyuan,*** overlying marine beds yield fusulinids that are of Visean age in western Europe and conodonts of the Datang Stage in south China,so that the age of the bed containing Cathaysiodendron as Visean,Early Carboniferous,is well *** a record of Cathaysiodendron is significant in terms of Carboniferous phyto-geography and the evolution of the Cathaysian Lepidophytes.A new species,Cathaysiodendron jingyuanense Wang&Wu *** described and a second one mentioned.

关键词： Cathaysiodendron Early Carboniferous Visean Cathaysian flora

The discovery of aeschnidiid nymphs (Aeschnidiidae, Odonata, Insecta)

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

chinese Science Bulletin 2000年第11期45卷 1031-1038页

作者： ZHANG Junfengnanjing Institute of geology and {2.,{3., nanjing 2.0008, China nanjing Institute of geology and {2. Chinese Academy of Sciences Nanjing China

Aeschnidiid nymphs are here first identified and described, and its phylogenetic relationship and bioecological characteristics are deduced. The nymphs known from China, Mongolia, Russia and Brazil and arranged in the family Aeschnidiidae are, in fact, unrelated to this group. All the known five chinese species in four genera which were erected based on fossil nymphs and placed in the family Gomphidae may be transferred in Aeschnidiidae and merged into one alone, the Sinaeschnidia cancellosa. It is a geographically widespread species from the 'Jehol biota' of East Asia and appeared in the latest Late Jurassic age.

关键词： Jehol biota Aeschnidiidae dragonfly nymphs.

Preface——Jurassic of China and Environs: Stratigraphy, Basin History, and Paleoenvironment

在线全文

学校读者我要写书评

暂无评论

Science China Earth sciences 2009年第12期52卷 1871-1872页

作者： SHA JinGeng LPS, nanjing Institute of geology and {2.,{3., nanjing 2.0008, China LPS Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China

The Jurassic is a geologically very complicated period in Earth history, spanning from 2.0 to 145 Ma. The Pangean supercontinent and even the Gondwana-land broke up, and the violent circum Paleo-Pacific (Yanshan) or... 详细信息

关键词： Preface and Paleoenvironment Stratigraphy Jurassic of China and Environs Basin History

Yangtzedonta and the early evolution of shelled molluscs

在线全文

学校读者我要写书评

暂无评论

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

作者： QIAN Yinanjing Institute of geology and {2.,{3., nanjing 2.0008, China nanjing Institute of geology and {2. 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.

Environmental characteristics of Mid-Holocene recorded by lacustrine sediments from Lake Daihai, north environment sensitive zone, China

在线全文

学校读者我要写书评

暂无评论

Science China Earth sciences 2006年第9期49卷 968-981页

作者： SUN Qianli1,2. ZHOU Jie1, SHEN Ji3. CHEN Peng1,2. WU Feng1,2.& XIE Xiuping1,2.1. State Key Lab of Loess and Quaternary geology, Institute of Earth Environment,{2., Xi’an 710075, China 2. Graduate University of{2., Beijing 10003., China 3. {3. Institute of Geography and Limnology,{2., nanjing 2.0008, China 1. State Key Lab of Loess and Quaternary geology Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 2. Graduate University of chinese academy of sciences Beijing 100039 China 3. nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China

Climate proxies, such as total organic carbon and nitrogen (TOC, TN), carbonate content (CaCO3., grain-size and pollen of the sediment core retrieved from enclosed Lake Daihai which lies in the north China environment sensitive zone are analyzed to reconstruct the environment evolution of the area based on high-resolution radiocarbon chronology. The results reveal that the TOC and TN contents of the sediments correlate well with pollen percentage and pollen flux variations during the Holocene, and both reach their peak values simultaneously at 6.7―3.5 ka BP (calendar age, 7.6―3.6 ka BP). Since 6.7 ka BP, both the CaCO3.and organic matter contents of the core have simultaneous variations, and their high values also occur during 6.7―3.5 ka BP. While during 9.0―6.7 ka BP (calendar age, 10―7.6 ka BP) relatively lower level of organic matter content and pollen flux corre- spond to the higher level of carbonate content. The above relations suggest that during 6.7―3.5 ka BP, the productivity and effective precipitation were greatly improved in the lake drainage area, and this would probably strengthen the hydrodynamic conditions, enhancing organic matter, pollen and carbonate inputs from terrestrial sources. Such processes would account for the enrichment of both organic matter and carbonate in the sediments. While during 9.0―6.7 ka BP, the lower level of or- ganic matter, pollen flux but high carbonate content show depressed productivity and declined vege- tation coverage. The higher carbonate content at this stage would have probably resulted from the higher evaporation ratio of the lake water under relatively drier climate conditions. Therefore, it is in- ferred that during 6.7―3.5 ka BP, the climate was more humid with abundant rainfalls and vegetation was more flourishing in the Lake Daihai area. This can be seen as Holocene Climate Optimum (HCO). As a result, this has evident discrepancies with the traditional notion that the HCO occurs at Early Holocene or early Mid

关键词： Lake Daihai, Mid-Holocene, lacustrine sediments, environmental characteristics.

Holocene grassland vegetation, climate and human impact in central eastern Inner Mongolia

在线全文

学校读者我要写书评

暂无评论

Science China Earth sciences 2005年第7期48卷 1025-1039页

作者： HUANG Fei1, Kealhofer Lisa2. XIONG Shangfa3.& HUANG Fengbao1 1. nanjing Institute of {2. and Paleontology,{2. {3. of sciences,nanjing 2.0008,China 2. Anthropology and Sociology Department,Santa Clara University,CA 95053.USA 3. Institute of {2. and Geophysics,{2. {3. of sciences,Beijing 10002.,China nanjing Institute of geology and Paleontology Chinese Academy of Sciences Nanjing 210008 China Anthropology and Sociology Department Santa Clara University CA 95053 United States Institute of geology and Geoohysics Chinese Academy of Sciences Beijina 100029 China

Phytolith and pollen preserved in the Taipusi Banner paleosol profile, central eastern Inner Mongolia, provide evidence of Holocene grassland vegetation, climate and human impact. The combined phytolith and pollen records reveal a major change in vegetation composition about 5000 a BP. Before 5000 a BP, the vegetation was dominated by Aneurolepidium chinese-Stipa grandis grassland of C4 grasses. After 5000 a BP, C4 grasses rapidly retreated, indicating a shift to colder and more arid conditions. The gradual invasion of Stipa krylovii, Ag-ropyron desertorum, Ephedra, Chenopodiaceae and Caragana reveal the onset of grassland degeneration. Between 10000 and 872. a BP, the Aneurolepidium chinese-Stipa grandis grassland included a small proportion of Artemisia shrub and Echionopos type plants, implying a strong winter monsoon and very weak summer monsoon. From 872. to 7000 a BP, C4 grasses were common, indicating a strengthening of the summer monsoon. Between 7000 and 5000 a BP, the Holocene thermal maximum was evident, with a significant expansion of C4 grasses and the presence of some trees (such as Pinus and Betula, and so on) in or near the study site. From 42.0?000 a BP, a sandy grassland of Artemisia and Agropyron desertorum together with Aster-type taxa occurred. Precipitation amelioration took place between {2.00 and 2.70 a BP, with a rapid development of Echinops type plants and a small expansion of C4 grasses. From 2.70 a BP to present, human activities accelerated the process of grassland degeneration.

关键词： phytolith and pollen records grassland environment change human impact Holocene central eastern Inner Mongolia.

Principal aspects of the Ordovician biotic radiation

在线全文

学校读者我要写书评

暂无评论

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 {2.,{3., nanjing 2.0008, 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

A restudy of Oryctocephalus indicus (Reed,1910)

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2006年第11期16卷 1177-1182页

作者： ZHAO Yuanlong~1**, YUAN Jinliang~2. PENG Shanchi~ 2.3., YANG Xinglian~1, PENG Jin~1, LIN Jihpai~4, and GUO Qingjun~5(1. College of Resource and Environment of Guizhou University, Guiyang 550003. China 2. {2. Institute of geology and {2.,{3., nanjing 2.0008, China 3. State Key Laboratory of Papaeobiology and Stratigraphy, {2. Institute of geology and {2., nanjing 2.0008, China 4. Department of Geological Science, Ohio State University, Columbus, OH 43.10, USA 5. Institute of Geochemistry,{3., Guiyang 550002. China) College of Resource and Environment of Guizhou University Guiyang 550003 China nanjing Institute of geology and {2. Chinese Academy of Sciences Nanjing 210008 China State Key Laboratory of Papaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Nanjing 210008 China Department of Geological Science Ohio State University Columbus OH 43210 United States Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

Restudy on morphology of Oryctocephalus indicus (Reed, 1910), based on specimens from Guizhou, China and Nevada USA, suggests that the subspecies regarded previously as Oryctocephalus indicus indicus (Reed, 1910), O. indicus latus Zhao et Yuan 2.02. and O. indicus kobayashi Saito, 193., are synonymous, and Oryctocephalus americanus Sundberg et McCollum, 2.03.is a similar form of O. indicus. Oryctocephalus indicus is rediagnosed as having a glabella that is subconical in outline and tapering forward slightly; a thorax that comprises 12.segments, and a small pygidium that bears 2.3.axial rings with a terminal piece and a postaxial ridge. Oryctocephalus indicus is widely distributed in eastern Guizhou and ranges through a great interval of Kaili Formation. Its first appearance is almost identical with these events of trilobite extinction-recovery occurring at the end of the Early Cambrian, the alternation of acritach assemblages, the change of trace elements (REE) and stable isotopes (carbon) at the Wuliu-Zengjiaya section. As one of the key forms for defining the traditional Lower-Middle Cambrian boundary (the base of Cambrian Series 3.and Stage 5 in the new Cambrian chronstratigraphic standard), O. indicus has received detailed study and has more advantages than other species such as Ovatoryctocara granulata Tchernysheva, 1962.or Arthricocephalus chauveaui Bergeron, 1899.

关键词： Oryctocephalus indicus restudy Kaili Formation Cambrian Guizhou China.

LATE SINIAN(TUBULAR) METAZOAN FOSSILS:CLOUDINA AND SINOTUBUL ITES FROM SOUTHERN SHAANXI

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

微体古生物学报 2001年第2期 193-198页

作者： CHEN Zhe and SUN Wei guo (nanjing Institute of geology and {2.,{3., nanjing 2.0008)