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A New Diverse Macrofossil Lagersttte from the Uppermost Ediacaran of Southwestern China 被引量:6
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作者 TANG Feng YIN Chongyu +2 位作者 LIU Pengju GAO Linzhi ZHANG Wenyan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第6期1095-1103,共9页
A new macrofossil Lagerstatte was discovered from the uppermost Ediacaran Jiucheng Member at Jinning and Jiangchuan of the eastern Yunnan, yielding numerous diverse well-preserved thallophyte macrofossils. These inclu... A new macrofossil Lagerstatte was discovered from the uppermost Ediacaran Jiucheng Member at Jinning and Jiangchuan of the eastern Yunnan, yielding numerous diverse well-preserved thallophyte macrofossils. These include the previously-known representatives of vendobionts, Vendotaenia and Tyrasotaenia, and the biggish multicellular benthos such as Chuaria-like and Tawuia- like fossiis, as well as Longfengshaniaceaens with diverse holdfast structures. There are still some other problematic macrofossils with peculiar configurations as well as uncertain relatives. The distinct dominance of the giant, unbranching thallophytes occasionally with holdfast structures distinguishes this assemblage from the other Ediacaran macrofossil Lagerstattes in the Doushantuo Formation at Miaohe, Wenghui and Lantian, and the contemporary assemblage in the Shibantan Member of Dengying Formation, Yangtze Gorges area. This paper outlines the characteristics of some of the multicellular macrofossils from the Jiucheng Member at Jiangchuan. They include some macrofossils with different types of holdfast structure, larger Chuaria-like and Tawuia-like morphology and questionable affinities as well. The discovery of greater diverse macrofossil assemblages from the Jiucheng Member of eastern Yunnan has further indicated that an important diversification and evolutionary radiation of metaphytes took place in the latest Ediacaran time. This radiation of largescale, benthic metaphyte along with phytoplankton was likely important contributors to the early Cambrian explosion of metazoans. 展开更多
关键词 eastern Yunnan Late Ediacaran Jiucheng Member diverse macrofossils
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New Data of Macrofossils in the Ediacaran Wenghui Biota from Guizhou,South China 被引量:3
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作者 WANG Ye WANG Yue +1 位作者 DU Wei WANG Xunlian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第5期1611-1628,共18页
The abundance and diversity of macrofossils in the Ediacaran have attracted much attention.The upper Doushantuo macrobiotas in South China,including the Miaohe biota from Hubei and the Wenghui biota from Guizhou,are m... The abundance and diversity of macrofossils in the Ediacaran have attracted much attention.The upper Doushantuo macrobiotas in South China,including the Miaohe biota from Hubei and the Wenghui biota from Guizhou,are mainly preserved as the carbonaceous compressions and dominated by macroscopic algae and metazoans.Here,we describe 10 genera and 10 species(including 6 new genera and species) of macrofossils from the Wenghui biota.At present,the Wenghui biota yields macrofossils in more than 31 genera and 33 species,excluding those given no image and established on a few unascertained specimens.Based on the occurrence and distribution of macrofossils in both Miaohe and Wenghui areas,the middle-late Ediacaran(back shales of the upper Doushantuo Formation) in South China can be subdivided into two assemblage biozones in biostratigraphy:(i) the Protoconites-Linbotulitaenia-Eoandromeda Anomalophton assemblage biozone characterized by abundant and diverse macrofossils and by the ranges of Protoconites,Linbotulitaenia and Anomalophton;and(ii) the Baculiphyca-Gesinella-Cucullus-Beltanelliformis assemblage biozone characterized by the acme of the longer macrofossils Baculiphyca and Gesinella,and by few shorter and discoidal macrofossils. 展开更多
关键词 macrofossilS Wenghui biota Doushantuo Formation EDIACARAN South China
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Ediacaran Macrofossils in Shunyang Valley,Sixi,Three Gorges District,Hubei Province,China 被引量:1
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作者 Roger Mason Yuejie Li +2 位作者 Kenan Cao Yu Long Zhen-Bing She 《Journal of Earth Science》 SCIE CAS CSCD 2017年第4期614-621,共8页
Previously undescribed Ediacaran macrofossils are documented in and close to a quarry southwest of Zigui in Shunyang Valley, near Sixi Village, Yangtze Three Gorges region, Hubei Prov- ince, China. Discoidal impressio... Previously undescribed Ediacaran macrofossils are documented in and close to a quarry southwest of Zigui in Shunyang Valley, near Sixi Village, Yangtze Three Gorges region, Hubei Prov- ince, China. Discoidal impressions, vendotaenids, and a new branching form occur in bedded carbon- ates through the entire 235 m thickness of the Dengying Formation. The quarry and nearby outcrops in the stream valley have significant potential for further discoveries of Ediacaran macrofossils. 展开更多
关键词 EDIACARAN macrofossil Dengying Formation Sixi.
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Two ribbon-like macrofossils in contrasting preservational styles from the Ediacaran-Cambrian interval
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作者 Yu-Lan Li Giovanni Mussini +4 位作者 Li-Jun Zhang Si-Cun Song Ming Li Ling Zhong Feng Tang 《Journal of Palaeogeography》 2025年第2期651-663,共13页
The fossil record of the latest Ediacaran and earliest Cambrian comprises diverse tubular and ribbon-like macrofossils of uncertain affinities,some of which could record early metazoans and macroalgae.This study compa... The fossil record of the latest Ediacaran and earliest Cambrian comprises diverse tubular and ribbon-like macrofossils of uncertain affinities,some of which could record early metazoans and macroalgae.This study compares two ribbon-like macrofossils typical of Ediacaran-Cambrian intervals,investigating their morphology,potential affinities,and biostratigraphic significance:Rugosusivitta,preserved as essentially twodimensional carbonaceous compressions,and Harlaniella,preserved as casts and molds.It is shown that the recently described Rugosusivitta orthogonia Tang et al.,2021 resembles the tube-like Harlaniella ingriana in its morphology,characterized by a combination of transverse ridges and longitudinal stripes separated into distinct parts of an elongate body.This combination of features challenges algal or protistan affinities,leaving open the possibility of metazoan origins.Both Rugosusivitta and Harlaniella likely represent body fossils rather than ichnofossils consistent with their preservation as either carbonaceous compressions or sediment-infilled tubes,respectively.By reconstructing the global distribution of Rugosusivitta and Harlaniella in different taphonomic windows,we suggest that these fossils record a coherent morphotype spanning the Ediacaran-Cambrian boundary. 展开更多
关键词 Rugosusivitta Harlaniella Ediacaran-Cambrian macrofossilS Ediacaran biota
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Climatic changes from the late Pliocene to middle Pleistocene in and around central Japan reconstructed from plant macrofossil assemblages 被引量:1
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作者 Arata MOMOHARA 《Chinese Science Bulletin》 SCIE EI CAS 1999年第S1期236-242,共7页
We used composition of plant macrofossil assemblages obtained mainly from theOsaka Group in central Japan to reconstruct the palaeoclimate between the late Pliocene (about 3.3m.y. B.P.) and the middle Pleistocene (abo... We used composition of plant macrofossil assemblages obtained mainly from theOsaka Group in central Japan to reconstruct the palaeoclimate between the late Pliocene (about 3.3m.y. B.P.) and the middle Pleistocene (about 0.4 m.y. B.P.). The warmest climate of the periodwas before 3.0 m.y. B.P. Cool-temperate elements increased and subtropical elements decreasedbetween 3 m.y. B.P. and 2.7 m.y. B.P., indicating the first climatic deterioration. The firstoccurrence of subarctic elements characterizes the Plio-Pleistocene boundary as a severe coldstage. After 1.1 m.y. B.P., climatic fluctuation occurred at less than 100,000 year intervals. Asevere cold stage occurred just after the Jaramillo event (about 0.8 m.y. B.P.). The warmest stagein the middle Pleistocene occurred at about 0.5 m.y. B.P. With it evergreen broad-leaved forestexpanded into central Japan. The climatic curves reconstructed from plant macrofossils parallel theclimatic changes reconstructed from loess - paleosol stratigraphy in Central China, radiolarianfaunal stratigraphy in the north Pacific deep sea drilling core, oxygen-isotope data in the NorthPacific, and pollen spectra in western Europe. 展开更多
关键词 Osaka Group PALEOCLIMATE PLANT macrofossilS PLIO-PLEISTOCENE
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Macrophyte community changes related to water level fluctuation and anthropogenic pressure in a floodplain lake in lower Huanghe River Basin,China since the 19^(th) century 被引量:1
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作者 Qinghui ZHANG Yingying CHEN +2 位作者 Shiyue CHEN Lin LIU Enfeng LIU 《Journal of Oceanology and Limnology》 2025年第3期848-864,共17页
Decades of species composition changes can lead to the eutrophication-driven loss of submerged macrophytes in shallow lakes.Investigating the mechanisms of these nature-and human driven changes is crucial for the rest... Decades of species composition changes can lead to the eutrophication-driven loss of submerged macrophytes in shallow lakes.Investigating the mechanisms of these nature-and human driven changes is crucial for the restoration and management of such lakes.To investigate the changes in aquatic macrophyte communities over the past two centuries,we analyzed macrofossils in sediments from a^(210)Pb-dated core obtained in Dongping Lake in the lower Huanghe(Yellow)River Basin,eastern China.Multiple factor analysis(MFA)revealed an association between macrophyte shifts and changes in various environmental stressors(invertebrates,grain size,geochemistry,and documented records),indicating that macrophyte community changes before 1960 were predominately driven by flood disturbances.Ever since,anthropogenic pollution and the construction of water conservancy projects have caused variations in hydrology and nutrients,leading to significant changes in the composition of macrophyte communities.Macrofossil data reveal a decline in diversity and pollution-intolerant species during the late 1980 s and the early 2000 s,which is indicative of eutrophication.We also found that the current environment of Dongping Lake exhibits a clear degeneration in emergent plants and a proliferation of macrophyte species associated with eutrophic conditions,which could be attributed to water level fluctuation and nutrient input due to the water supply from the eastern route of the South-to-North Water Diversion Project as well as climate warming.Our results provide valuable insights for assessing ecosystem health and the restoration and management of Dongping Lake and similar lakes in the Huanghe River region and elsewhere. 展开更多
关键词 aquatic macrophyte Dongping Lake PALEOECOLOGY plant macrofossil restoration Huanghe River
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长白山西侧哈泥沼泽表面湿度的多指标记录及其可能的驱动因素 被引量:14
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作者 赵红艳 李鸿凯 +2 位作者 韩毅 卜兆君 王升忠 《第四纪研究》 CAS CSCD 北大核心 2014年第2期434-442,共9页
本文采用半定量化的植物大化石技术、腐殖化度分析和烧失量方法,重建长白山地哈泥沼泽表层50cm湿度变化过程,探讨控制沼泽表面湿度变化的主导因素,并试图揭示该地过去175年的气候变化,考察植物大化石在大陆性气候下的敏感性。根据^(210... 本文采用半定量化的植物大化石技术、腐殖化度分析和烧失量方法,重建长白山地哈泥沼泽表层50cm湿度变化过程,探讨控制沼泽表面湿度变化的主导因素,并试图揭示该地过去175年的气候变化,考察植物大化石在大陆性气候下的敏感性。根据^(210)Pb技术和AMS^(14)C定年法确定剖面年代。结果表明,哈泥沼泽表层50cm以泥炭藓泥炭为主,植物大化石除趋势分析揭示植被演替是由水位变化造成的,且3种指标揭示的哈泥沼泽表面湿度变化趋势基本一致,即从0~22cm(约公元1983~2008年)表面湿度明显偏大;22~34cm(约1925~1982年)处于干燥时期;34~50cm(约1834~1924年)沼泽表面湿度较高。通过与最近的靖宇站的气象数据和长春地区的湿润指数对比,发现3种指标重建的表面湿度与降水数据或者湿润指数比较吻合,与温度关系次之,沼泽表面湿度增大发生在夏季降水和年降水均高的年份。由此推测,降水可能是引起沼泽表面湿度变化的主要因素。结论也说明植物大化石和腐殖化度在大陆性气候条件下对沼泽表面湿度变化仍然反应敏感。 展开更多
关键词 气候代用指标 植物大化石 腐殖化度 烧失量 除趋势对应分析 泥炭
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华南伊迪卡拉(震旦)系顶部建阶层型和界线层型新资料 被引量:12
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作者 唐烽 高林志 +2 位作者 尹崇玉 王约 顾鹏 《地质通报》 CAS CSCD 北大核心 2015年第12期2150-2162,共13页
新元古代与寒武纪之交,即伊迪卡拉纪—寒武纪过渡期,是地球历史上一个重大的地质突变期,出现了一系列地质环境变化事件和生物快速演化事件。云南东部位于扬子地区西南缘,在前寒武纪—寒武纪过渡期属于开放式浅水台地至台缘斜坡环境,是... 新元古代与寒武纪之交,即伊迪卡拉纪—寒武纪过渡期,是地球历史上一个重大的地质突变期,出现了一系列地质环境变化事件和生物快速演化事件。云南东部位于扬子地区西南缘,在前寒武纪—寒武纪过渡期属于开放式浅水台地至台缘斜坡环境,是中国伊迪卡拉(震旦)系顶部与底寒武统基本连续沉积的典型地区,也曾是中国震旦系与寒武系界线层型候选剖面所在地。近年来,在此新发现了更为丰富的宏体藻类化石、遗迹化石和伊迪卡拉生物群的疑似后生动物化石等(江川生物群),以及大量以条带状Shaanxilithes为代表的宏体化石层。相关剖面自下而上从灯影组至磷矿沉积层(中谊村段)出露有连续的宏体化石记录,研究后可以细分伊迪卡拉系顶部灯影峡阶的化石带,并与底寒武统晋宁阶、梅树村阶对接,具有作为标准层型剖面的较大潜力,为伊迪卡拉纪末期年代地层单位的建阶分层、对比及确立层型剖面,以及与寒武纪最早期年代地层的界线划分提供了更为理想的标准。 展开更多
关键词 前寒武纪—寒武纪过渡层 宏体化石组合 标志化石 末阶层型 界线层型
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滇东埃迪卡拉(震旦)系顶部旧城段多样宏体化石群的发现 被引量:12
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作者 唐烽 尹崇玉 +2 位作者 刘鹏举 王自强 高林志 《古地理学报》 CAS CSCD 2007年第5期533-540,共8页
在中国云南东部晋宁、江川地区的埃迪卡拉(震旦)系顶部灯影组旧城段,新发现了多样的宏体化石群,其中除了丰富的Vendotaenia与Tyrasotaenia类化石以外,以形体较大的Tawuia类和Longfengshaniaceae科等具固着构造的底栖多细胞藻类化石占据... 在中国云南东部晋宁、江川地区的埃迪卡拉(震旦)系顶部灯影组旧城段,新发现了多样的宏体化石群,其中除了丰富的Vendotaenia与Tyrasotaenia类化石以外,以形体较大的Tawuia类和Longfengshaniaceae科等具固着构造的底栖多细胞藻类化石占据优势,另有一些形态奇特、亲缘关系不明的宏体化石,该组合与华南陡山沱组和灯影组石板滩段的宏体化石组合存在着明显的差别。依据形态特征,概述了部分产自江川旧城段的具有不同类型固着构造的底栖藻类和归属不明的宏体化石特征。滇东地区旧城段形态多样的宏体藻类化石的发现,进一步表明埃迪卡拉纪末期存在后生植物的多样化发展。这一时期浮游微生物和后生植物的共同繁盛可能为早寒武世"澄江生物群"的爆发奠定了生态基础。 展开更多
关键词 滇东地区 埃迪卡拉(震旦)系 旧城段 宏体化石组合
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华南新元古代宏体化石特征及生物地层序列 被引量:7
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作者 唐烽 尹崇玉 +2 位作者 刘鹏举 高林志 王自强 《地球学报》 EI CAS CSCD 北大核心 2009年第4期505-522,共18页
华南的新元古代地层(780~542 Ma)保存有许多经典的地层剖面和丰富的宏体化石记录,一直是我国新元古代,特别是南华系和震旦(伊迪卡拉)系地层对比的标准区域。本项研究重新考察了部分重要的标准剖面和化石点,重点采集了近年来开始研究的... 华南的新元古代地层(780~542 Ma)保存有许多经典的地层剖面和丰富的宏体化石记录,一直是我国新元古代,特别是南华系和震旦(伊迪卡拉)系地层对比的标准区域。本项研究重新考察了部分重要的标准剖面和化石点,重点采集了近年来开始研究的云南"江川生物群",贵州江口"翁会生物群"的宏体化石,在总结了前人研究成果的基础上,集成了最新的研究进展,综合记录了华南晚新元古代地层中的宏体化石特征,组合面貌,据此提出了华南晚新元古代生物地层序列。宏体化石的记录表明在这一时期伴随着显著的气候和环境变化,发生了一系列重要的生物演化事件,多细胞的宏观后生动、植物普遍出现了组织分化,器官形成和发育创新,以及生物结构和功能的进一步复杂多样化。这种多样化的发展大体可以划分为三个阶段,分别以震旦(伊迪卡拉)纪的三个宏体化石组合为代表:(1)Anhuiphyton—Thallophyca—Paramecia宏体藻类化石组合,(2)Enteromorphites—Doushantuophyton—Eoandromeda—Sinospongia宏体化石组合,(3)Paracharnia—Gaojiashania—Cloudina—Longfengshania宏体化石组合。由于华南震旦纪宏体化石具有较为独特的组合面貌,与国外末次冰期后大量出现的伊迪卡拉型生物群(阿瓦隆生物群,庞德/白海生物群和纳马生物群)如何对比,还有待深入的研究。本文还重点讨论了华南地区新元古代宏体化石的南、北方对比问题。 展开更多
关键词 华南 新元古代 宏体化石组合 生物地层序列 地层对比
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华北克拉通东部新元古代宏体化石生物地层序列 被引量:9
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作者 唐烽 尹崇玉 +3 位作者 高林志 刘鹏举 王自强 陈寿铭 《地质论评》 CAS CSCD 北大核心 2009年第3期305-317,共13页
华北克拉通东部是中国晚前寒武纪地层出露最为完整、连续的地区,特别是华北克拉通东缘连续出露了新元古代自老至新的全部地层,是对比和衔接中国南、北方晚前寒武纪地层的关键地区。在该地区所发现和建立的宏体化石群——"龙凤山生... 华北克拉通东部是中国晚前寒武纪地层出露最为完整、连续的地区,特别是华北克拉通东缘连续出露了新元古代自老至新的全部地层,是对比和衔接中国南、北方晚前寒武纪地层的关键地区。在该地区所发现和建立的宏体化石群——"龙凤山生物群"、"辽南生物群"和"淮南生物群"可能是新元古代"南华大冰期"前后较为独特的生物群落,其中相当部分可能归属于多细胞后生动物和多细胞藻类,是地球早期生命景观的重要代表。因此,对这些新元古代早期生物群的研究将可能揭示比陡山沱期更早的多细胞后生动植物的演化面貌,在演化生物学上意义重大。近年来,在地调项目的资助下,开展了华北克拉通东部地区的新元古代年代地层及生物地层的研究。本文综合现有资料,详细记述了华北克拉通东部(燕山地区和辽南、徐淮地区)含宏体化石的新元古代地层及其宏体化石特征、组合面貌和生物地层序列。同时,依据宏体化石记录,探讨了中国新元古代地层的对比问题。 展开更多
关键词 华北克拉通东部 新元古代 宏体化石 生物地层序列 地层对比
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华南伊迪卡拉纪宏体生物群的古地理分布及意义 被引量:10
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作者 唐烽 高林志 王自强 《古地理学报》 CAS CSCD 北大核心 2009年第5期524-533,共10页
伊迪卡拉纪(635—542,Ma)是前寒武纪全球大规模末次冰期(Marinoan)结束后至寒武纪"生命大爆发"之前一段重要的地质时期,由于受到新元古代气候和环境剧变的影响,真核生物乃至多细胞生物迅速演化、分异,出现显著的适应辐射。中... 伊迪卡拉纪(635—542,Ma)是前寒武纪全球大规模末次冰期(Marinoan)结束后至寒武纪"生命大爆发"之前一段重要的地质时期,由于受到新元古代气候和环境剧变的影响,真核生物乃至多细胞生物迅速演化、分异,出现显著的适应辐射。中国华南的伊迪卡拉系——震旦系陡山沱组和灯影组及其相当地层代表着这一特殊地史时段的沉积,地层记录完整,岩相环境多样,化石产出丰富,是深入研究伊迪卡拉(震旦)纪(Ediacaran/Sinian)地层划分及全球对比、探讨早期多细胞生物起源和辐射的理想地区之一。其中,扬子台地边缘相地层中出露丰富的宏体化石材料,分异显著,具有较为独特的组合面貌。近年取得的研究成果表明华南宏体化石群中也含有澳洲伊迪卡拉生物群和俄罗斯白海生物群的典型分子。作者总结了前人关于华南伊迪卡拉纪岩相古地理的研究成果;重点展示了近年来开始研究的贵州江口"翁会生物群"、云南"江川生物群"的宏体化石;简要记述了华南伊迪卡拉系中以"庙河生物群"为代表的若干宏体生物群的古地理位置及其宏体化石组合特征,据此提出了华南伊迪卡拉纪丰富多样的宏体生物群基本发育在扬子台地边缘碎屑岩至碳酸盐岩相的过渡带和斜坡带;各生物群宏体化石的组合面貌受沉积微相的制约,存在一定的变化规律。宏体化石记录表明在这一时期,伴随着显著的气候和环境变化,不仅发生了一系列重要的生物演化事件,比如:多细胞藻类和后生动物普遍开始出现多样化发展,为寒武纪生命的演化辐射奠定了生态基础;而且在华南地区已经形成了一个全新的浅海生态系统,以浮游和底栖真核藻类为主的海洋初级生产者大量繁盛,尤其是丰富的多细胞藻类可能成为前寒武纪末期至寒武纪早期主要的生烃植物类群。 展开更多
关键词 华南 伊迪卡拉(震旦)纪 宏体化石组合 岩相古地理 古生态
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华南伊迪卡拉纪类水母化石新发现(英文) 被引量:2
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作者 唐烽 钟玲 +2 位作者 金幸生 郭东辉 尹崇玉 《地质通报》 CAS CSCD 北大核心 2016年第1期1-9,共9页
华南黔东北地区伊迪卡拉系陡山沱组黑色页岩中产出丰富多样的海相底栖宏体化石组合,其中包含2个新属种Kullingia rotadiscopsis sp.nov.和Eoaequorea xingi gen.&sp.nov.。新类别具有保存清晰的碳质同心环纹和辐射状纹饰,形态上相... 华南黔东北地区伊迪卡拉系陡山沱组黑色页岩中产出丰富多样的海相底栖宏体化石组合,其中包含2个新属种Kullingia rotadiscopsis sp.nov.和Eoaequorea xingi gen.&sp.nov.。新类别具有保存清晰的碳质同心环纹和辐射状纹饰,形态上相似于国外广泛分布在碎屑岩和碳酸盐岩中的伊迪卡拉纪典型的圆盘状化石,例如Aspidella,Ediacaria,Cyclomedusa,Eoporpita,Ovatoscutum,Spriggia,Kullingia等。上述化石在国外几乎都保存为印痕,近年来多被解释为不明亲缘底栖生物的圆形固着痕迹或抓痕、圆环状扫痕等,华南陡山沱组碳质压膜保存的圆盘状宏体化石显然不支持该解释。目前,还没有充分的证据表明华南新发现的碳膜化石与国外形态类似的印痕化石如Kullingia和Aspidella具有相同的亲缘关系,但支持将华南化石归属为可能最早的浮游型水螅水母。 展开更多
关键词 伊迪卡拉纪 圆盘状宏体化石 华南 似水母生物
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Fossil Association from the Lower Cambrian Yanjiahe Formation in the Yangtze Gorges Area,Hubei,South China 被引量:11
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作者 GUO Junfeng LI Yong +7 位作者 HAN Jian ZHANG Xingliang ZHANG Zhifei OU Qiang LIU Jianni SHU Degan Shigenori MARUYAMA Tsuyoshi KOMIYA 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第6期1124-1132,共9页
Apart from previously reported Small Shelly Fossils (SSFs), a macroscopic fossil assemblage, comprising abundant algae, cone-shaped tubular fossil forms, and probable impressions of a megascopic metazoan, comes from... Apart from previously reported Small Shelly Fossils (SSFs), a macroscopic fossil assemblage, comprising abundant algae, cone-shaped tubular fossil forms, and probable impressions of a megascopic metazoan, comes from the Lower Cambrian Yanjiahe Formation in the Yangtze Gorges area of western Hubei Province, south China. The visible fossils are preserved in thinlaminated siltstone or muddy siltstone intercalated between 8-15 ram-thick carbonate deposits, probably representing sedimentary settings of a constrained local depression in the shallow water carbonate platform during the Early Cambrian Meishucunian Stage. The macroscopic fossil association provides significant fossil evidence about the evolution of life from the late Precambrian to the 'Cambrian explosion' interval. 展开更多
关键词 macrofossil association Yanjiahe Formation Lower Cambrian Yangtze Gorges Area Hubei Province
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峡东区上震旦统陡山沱组发现宏体化石 被引量:50
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作者 陈孟莪 肖宗正 《地质科学》 CAS CSCD 北大核心 1991年第4期317-324,T006,共9页
峡东区上震旦统陡山沱组顶部发现宏体化石,包括高级藻类和蠕虫类,共8属10种,其中有些分类未定的化石。这从形态学上证明了后生藻类植物的分化及第一次为后生动物在陡山沱期的存在提供了可信的证据。这是一次有突破性的发现。
关键词 宏体化石 蠕虫类 藻类 震旦纪
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浅水湖泊孢粉和植物残体对水生植被的表现率 被引量:2
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作者 赵艳 李佳佳 Carl Sayer 《长江流域资源与环境》 CAS CSSCI CSCD 北大核心 2005年第4期456-459,共4页
研究浅水湖泊中植物残体对水生植物的表现率,用于重建近代水生植被历史,可为治理湖泊富营养化,恢复湖泊生态环境提供依据。研究选址为英国北部的一个小湖泊,通过水生植物调查及表层沉积物中植物残体和孢粉分析,及地理信息系统方法定量... 研究浅水湖泊中植物残体对水生植物的表现率,用于重建近代水生植被历史,可为治理湖泊富营养化,恢复湖泊生态环境提供依据。研究选址为英国北部的一个小湖泊,通过水生植物调查及表层沉积物中植物残体和孢粉分析,及地理信息系统方法定量研究植物残体对水生植物的表现率。结果表明:沉积物中植物残体精确地反映了植物优势种的存在;植物和植物残体的关系是很复杂的,有些植物在残体中表现率明显超高,而有些表现率偏低;应把叶子和其它非繁殖植株部分作为恢复近代多年生植物历史依据;植物残体传输性较差,主要集中在植物母体附近;利用植物残体与孢粉分析相结合的方法能更准确地重建植被历史。 展开更多
关键词 植物残体 水生植被 浅水湖泊 湖泊富营养化 湖泊生态环境 水生植物 孢粉分析 表层沉积物 多年生植物 植物调查 定量研究 系统方法 地理信息 历史 优势种 传输性 近代 重建 恢复 选址
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中国晚前寒武纪的宏体化石概观 被引量:16
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作者 陈孟莪 《地质科学》 CAS CSCD 北大核心 1989年第3期244-255,共12页
本文综述了目前中国晚前寒武纪地层中所发现的宏体化石,从18亿年起直到6亿年左右。蓟县剖面高于庄组(14亿年)中发现Grypanta等大化石,再次证明生物演化大阶段的世界性。包括后生动物实体化石在内的淮南生物群可能是前冰期的,也就是先伊... 本文综述了目前中国晚前寒武纪地层中所发现的宏体化石,从18亿年起直到6亿年左右。蓟县剖面高于庄组(14亿年)中发现Grypanta等大化石,再次证明生物演化大阶段的世界性。包括后生动物实体化石在内的淮南生物群可能是前冰期的,也就是先伊迪卡拉期的。震旦纪晚期的西陵峡生物群,现有伊迪卡拉期的典型分子,又有丰富的蠕虫管和高级的红藻、绿藻类。蠕虫管的大量出现预告了带硬部动物时代的到来。 展开更多
关键词 前寒武纪 宏体 化石 生物群
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Vegetation Development and Water Level Changes in Shenjiadian Peatland in Sanjiang Plain,Northeast China 被引量:10
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作者 WANG Chunling ZHAO Hongyan WANG Guoping 《Chinese Geographical Science》 SCIE CSCD 2015年第4期451-461,共11页
This paper documents a 7800-year proxy record from the Shenjiadian peatland on the Sanjiang Plain in Northeast China.High-resolution plant macrofossil and colorimetric humification methods were used to reconstruct the... This paper documents a 7800-year proxy record from the Shenjiadian peatland on the Sanjiang Plain in Northeast China.High-resolution plant macrofossil and colorimetric humification methods were used to reconstruct the vegetation and hydrologic history from a 193 cm-long sedimentary profile.Detrended correspondence analysis(DCA) was applied to transform the raw plant macrofossil data into latent indices of peatland water level.The vegetation community transited from an Equisetum fluviatile community to a Carex lasiocarpa community at approximately 3800 cal yr BP and was followed by a Carex-shrub community at approximately 480 cal yr BP.Based on the plant macrofossil DCA axis 1 scores and humification values,we distinguished four hydrologic periods:a wet period from 7800 cal yr BP to 4500 cal yr BP,dry periods up to 1600 cal yr BP,drier periods until 300 cal yr BP,and the driest period from 300 cal yr BP until the present.Through a comparison with other climate records,we suggest that the East Asian summer monsoon(EAM) was the main driving force for vegetation and water level changes to the Shenjiadian peatland through its impacts on precipitation. 展开更多
关键词 plant macrofossils humification Holocene peatland Northeast China
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High-resolution patterns of palaeoenvironmental changes during the Little Ice Age and the Medieval Climate Anomaly in the northwestern Iberian Peninsula 被引量:2
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作者 Daniel Castro Martin Souto +4 位作者 Maria Isabel Fraga Eduardo Garcia-Rodeja Sebastian Perez-Diaz Jose Antonio Lopez Saez Xabier Pontevedra-Pombal 《Geoscience Frontiers》 SCIE CAS CSCD 2020年第5期1461-1475,共15页
to identify plant macrofossils,estimate peat humification and calculate hydroclimatic indices based on current bog species,with the overall aim of determining the climate conditions associated with evolution of the bo... to identify plant macrofossils,estimate peat humification and calculate hydroclimatic indices based on current bog species,with the overall aim of determining the climate conditions associated with evolution of the bog during the Medieval Climate Anomaly and the Little Ice Age.These proxies,together with historical and climate data,proved to be good indicators of the changes in bog surface wetness.Analysis:of the core led to identification of 9 different periods:two corresponding to the so-called Medieval Climate Anomaly(930 to 1345 AD,1075–665 calibrated years before present[cal.yr BP]);four corresponding to the Little Ice Age(1345 to 1905 AD;665–105 cal yr BP);and three corresponding to the last century(1905 to 2000 AD).The findings revealed a generally dry climate that lasted until the 14th century,followed by a transition to a long period with a more humid,but characteristically very variable climate,which ended at the beginning of the 20th century and was followed by a rapid transition to more humid conditions and finally,a change to drier conditions.The Medieval Climate Anomaly was indicated by the abundance of dry-adapted mosses(Leucobryum glaucum,Hypnum cupressiforme)and characterized by warm dry conditions and high levels of peat humification,with alternating wet phases.The LIA period was dated by a large abundance of Sphagnum species(an indicator of wetness)and a gradual increase in the humification index.However,four different climate phases were differentiated in this period.High-resolution reconstruction of the evolution of the CVM bog and the multiproxy approach have together enabled a more detailed identification of climatic variations in this area,which are generally consistent with the global models,as well as better definition of the elusive climatic oscillations in the last millennium and confirmation of the importance of local modulation of global models.The study provides new information and a detailed chronology of climatic events that will help to refine local modulation of the climate evolution model in the still quite unexplored region of the NW Iberian Peninsula,a key area for understanding the paleoclimatic dynamics in SW Europe. 展开更多
关键词 Last millennium Raised bog Plant macrofossil Humification analysis Southwest Europe Climate change
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甘肃窑街中侏罗世Coniopteris lanzhouensis的微细构造研究 被引量:3
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作者 辛存林 季健健 王露菡 《微体古生物学报》 CSCD 北大核心 2017年第4期428-439,共12页
本文对甘肃窑街中侏罗统窑街组采集的真蕨类化石标本进行了描述,通过与相似种的小羽片的形态和大小、羽片排列和间距、羽轴宽度、孢子囊群形态等特征对比,明确该化石植物为Coniopteris lanzhouensis。通过实验分析揭示了Coniopteris lan... 本文对甘肃窑街中侏罗统窑街组采集的真蕨类化石标本进行了描述,通过与相似种的小羽片的形态和大小、羽片排列和间距、羽轴宽度、孢子囊群形态等特征对比,明确该化石植物为Coniopteris lanzhouensis。通过实验分析揭示了Coniopteris lanzhouensis的原位孢子基本特征:孢子为四面体,赤道轮廓呈圆三角形,顶角钝圆,三边线微凸或微凹;具三射线,三射线平直且较窄,长度为孢子半径的3/4或延伸至孢子边缘,顶端具与其垂直的褶皱;外壁光滑,壁薄,极面观直径30-40μm,平均约33μm;孢子的颜色以浅黄色为主。明确了Cibotiumspora juncta可能是Coniopteris lanzhouensis的孢子,后者为前者的母体植物。 展开更多
关键词 Coniopteris lanzhouensis 原位孢子植物大化石 中侏罗世 窑街组 甘肃
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