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Science China Earth Sciences 2004年第10期47卷 880-885页

作者： YIN Leiming BIAN Lizeng yuan xunlai Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China Department of Earth Sciences Nanjing University Naniing 210093 China Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China

Most previously reported Mesoproterozoic (1600-1000 Ma) fossils are from silicified carbonates, and they are commonly small in size (15-20 μm, ranging from coccoids to fila- ments in morphology. Many of them can be interpreted as cyanobacteria. Carbonaceous shales represent another source of palaeontological information of the Mesoproterozoic biosphere. Sphaeromorphic and acanthomorphic acritarchs, as well as filamentous fossils, are common in many Mesoproterozoic shales. Here we report an unusual assemblage of tubular fossils from the Meosproterozoic Ruyang Group in Shanxi, North China. Some of these tubes are branched. Others bear annular-helical thickening that might be represented by one extinct algae to adapt to a desiccating environment.

关键词： Shanxi, Mesoproterozoic, tubular branching alga, helical tubes.

Paleoproterozoic glaciation: Evidence from carbon isotope record of the Hutuo Group, Wutai Mountain area of Shanxi Province, China

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Chinese Science Bulletin 2011年第27期56卷 2922-2930页

作者： KONG FanFan yuan xunlai ZHOU ChuanMing School of Resource and Earth Science China University of Mining and Technology Xuzhou 221008 China State Key Laboratory of Paleobiology and Stratigraphy Nanjing Institute of Geology and Paleontology Chinese Academy of Sciences Nanjing 210008 China

Palaeoproterozoic 全球冻结成冰(2.3 Ga ) 可以是地球历史上的第一个雪球地球事件。诺思中国暴露得好沉积存款这次有最小的 postdepositional 的时期改变。一个冻结成冰事件的沉积证据然而一直在缺乏。这里，我们在 Wutai 山区分析了 P... 详细信息

Palaeoproterozoic 全球冻结成冰(2.3 Ga ) 可以是地球历史上的第一个雪球地球事件。诺思中国暴露得好沉积存款这次有最小的 postdepositional 的时期改变。一个冻结成冰事件的沉积证据然而一直在缺乏。这里，我们在 Wutai 山区分析了 Paleoproterozoic Hutuo 组(2.52.2 Ga ) 的碳同位素作文，山西省，诺思中国。我们的数据表演，在里面一对更年轻的 chronostratigraphic 顺序更旧，(1 ) 积极 13Ccarb 在 Doucun 亚群的 Dashiling 形成珍视(3.2 ～ 1.0， VPDB ) ；(2 ) 在 13Ccarb 的减少从 Wenshan 形成珍视到中间的 Daguandong 形成(从 2.0 to1.2 ) ，在哪个时间期间 stromatolites 的出现衰退了；(3 ) 在上面的 Daguandong 形成的一次显著否定旅行，在 Daguandong 和 Huaiyincun 形成的边界(从 1.4 ～ 3.3 ) ，在 stromatolites 消失了的地方；并且(4 ) 13Ccarb 的渐渐的增加在 Beidaxing 和 Tianpengnao 形成珍视(从 1.2 ～ 1.4 ) ，在哪个期间时间 stromatolites 回来了。我们主张否定的碳同位素旅行从 Jianancun 形成记录了到 Hutuo 组的中间的 Daguandong 形成可以是对 Palaeoproterozoic 全球冻结成冰的诺思瓷器反应。

关键词：碳同位素记录冰期事件古元古代中国北方五台山区山西省证据滹沱河

Ediacaran integrative stratigraphy and timescale of China

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Science China Earth Sciences 2019年第1期62卷 7-24页

作者： Chuanming ZHOU xunlai yuan Shuhai XIAO Zhe CHEN Hong HUA CAS Key Laboratory of Economic Stratigraphy and Palaeogeography Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and Palaeoenvironment Chinese Academy of Sciences State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and Palaeoenvironment Chinese Academy of Sciences Department of Geosciences Virginia Tech Blacksburg State Key Laboratory of Continental Dynamics Department of Geology Northwest University

Ediacaran successions occur widely in various depositional facies in South China and yield a series of fossil Lagerst?tten, providing a complete fossil record for the evolution of marine ecosystems after the terminal Cryogenian global glaciation. Carbonate-dominated Ediacaran successions in shallow water facies in South China record a nearly complete δ^(13)C profile that may reflect variations of marine carbon isotopic composition during the Ediacaran Period. The Ediacaran fossils andδ^(13)C profiles from South China permit stratigraphic correlation and subdivision of the Ediacaran strata. Based on biostratigraphic, chemostratigraphic, and geochronometric data from the Ediacaran successions in South China, we propose that the Ediacaran System in China can be subdivided into two series, with three stages in each series. The lower series is characterized by acanthomorphic acritarchs and the upper series by Ediacara-type macrofossils, and the two series are separated by the declining limb of a pronounced δ^(13)C negative excursion(EN3) in the upper Doushantuo Formation. The basal boundary of Stage1 is the same as the basal boundary of Ediacaran System, which has been defined at the base of the cap carbonate unit. Stage 2 represents the first radiation of Ediacaran microscopic organisms, with δ^(13)C feature representing by positive values(EP1). The base of the Stage 2 is placed at the first appearance level of a spiny acritarch species. Stage 3 is characterized by the occurrence of more diverse acritarchs and δ^(13)C feature EP2, with its basal boundary defined by a δ^(13)C negative excursion(EN2) occurring in the middle Doushantuo Formation. The basal boundary of Stage 4 is the same as the upper series. Stage 5 is marked by the occurrence of macrfossils of Miaohe biota, and its lower boundary can be placed at the level where δ^(13)C values transition from positive to negative in MNE, or the first appearance level of macrofossils of the Miaohe biota. Stage 6 is charact

关键词： Ediacaran Biostratigraphy Chemostratigraphy Stratotype section South China

Phosphatized biotas from the Neoproterozoic Doushantuo Formation on the Yangtze Platform

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Chinese Science Bulletin 2002年第22期47卷 1918-1924页

作者： ZHOU Chuanming yuan xunlai XIAO Shuhai Nanjing Institute of Geology and Paleontology Chinese Academy of SciencesNanjing 210008China Department of Geology TWane UniversityNew OrleansLA 70118USA

The Doushantuo Formation in South China was deposited after the Nantuo glaciation but before the evolution of complex Ediacaran metazoans. It contains multiple taphonomic windows, in its cherts, carbonaceous shales, and phosphorites, onto the late Neoproterozoic biosphere. The phosphatic window is unusually clear; Doushantuo phosphorites at Weng’an (Guizhou Province) are known to exquisitely preserve a multitude of single-celled eukaryotes, muiticellular algae, and microscopic animals. Our recent survey reveals that, in addition to the now famous Weng’an locality, Doushantuo phosphorites at Baokang (Hubei), Chadian (Shaanxi), and Shangrao (Jiangxi) also contain diverse eukaryotes preserved at the cellular level. All these phosphorites were deposited in shallow-water environments, typically above fair weather wave base and close to ancient islands. Along with Doushantuo cherts and shales, these phosphorites give us a clearer and more complete picture of late Neoproterozoic biological evolution: there

关键词： Neoproterozoic Doushantuo Formation phosphorite phosphatized biota eukaryotic fossils Yangtze Platform.

New observations on spicule-like structures from Dou-shantuo phosphorites at Weng'an,Guizhou Province

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Chinese Science Bulletin 2001年第21期46卷 1828-1832页

作者： Leiming Yin Shuhai Xiao xunlai yuan Nanjing Institute of Geology and Paleontology Chinese Academy of Sciences Nanjing China Department of Geology Tulane University New Orleans USA

Doushantuo phosphorites at Weng’an, Guizhou Province, provide a unique opportunity for the study of early evolution of multicellular organisms, including metazoans. Our light microscope and SEM observations, however, do not substantiate a sponge spicule interpretation of spicular structures. No convincing axial canals have been seen in the observed spicule population. Instead, the coexistence of some monaxonal spicules with clearly diagenetic crystal fascicles and dumbbells suggest that these monaxons may also be diagenetic in origin. Our preliminary EDS analyses detect no significant silicon in spicule-containing intraclasts (including abiotic clasts and fragments of sphaeromorphic acritarchs and algal thalli), that contain abundant monaxonal spicular structures. We, therefore, believe that the evidence for a sponge spicule interpretation of the Doushantuo spicular structures are at best ambiguous at present; these alleged sponge spicules are indistinguishable from coexistent diagenetic crystals.

关键词： Doushantuo Formation Neoproterozoic Guizhou phosphorite sponge.

Cell wall ultrastructures of the Proterozoic acritarch Leiosphaeridia asperata and their implications for biological affinity

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Science China Earth Sciences 2010年第12期53卷 1750-1755页

作者： GONG Miao ZHOU ChuanMing YIN LeiMing yuan xunlai WANG ChunZhao State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China Hunan Geological Museum Changsha 410007China

Abundant sphaeroidal acritarch Leiosphaeridia asperata,with vesicle size ranging from 13 to 360 μm,occurred in the Proterozoic Liulaobei Formation shales in Huainan,Anhui ***/SEM studies of these sphaeroidal acritarchs have revealed complex ultrastructures,including ridges,bands,and possible trilaminar structures(TLS).Ridges,spaced ~1 μm apart,are distributed regularly on the vesicle internal surface of one *** specimens have alternating electron-dense and electron-tenuous bands that are perpendicular to vesicle *** specimens have trilaminar structures(TLS),while a few others have both bands and *** wall ultrastructures provide evidence that the Liulaobei leiosphaerids are of green *** variation in wall ultrastructures may represent various stages in a life cycle or developmental phases in the cyst formation analogous to some modern chlorophyceaen microalgae.

关键词： ultrastructure affinity Leiosphaeridia asperata Proterozoic Liulaobei Formation

The earliest Foraminifera from southern Shaanxi,China

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Science China Earth Sciences 2010年第12期53卷 1756-1764页

作者： HUA Hong CHEN Zhe yuan xunlai XIAO ShuHai CAI YaoPing Early Life Institute State Key Laboratory of Continental DynamicsDepartment of GeologyNorthwest UniversityXi’an710069China Nanjing Institute of Geology and Palaeontology Chinese Academy of SciencesNanjing 210008China Department of Geosciences Virginia Polytechnic Institute and State UniversityBlacksburgVirginia24061USA

Vase-shaped microfossils(VSMs) described herein mainly occur as isolated individuals in thin bedded siltstone and silty carbonate of the Gaojiashan Member of the upper Ediacaran Dengying Formation(ca.551-541 Ma).Although these fossils are abundant,chained tests or other types of colonial aggregates have not been *** in the siltstones can easily be isolated from the host rocks by ultrasonic *** with the co-occurring fossils Gaojiashania and Conotubus,VSMs are rarely pyritized,yet they are always three-dimensionally persevered with little deformation,suggesting that their tests were sturdy and possibly *** observation and elemental mapping reveal two types of tests that are respectively calcareous and siliceous in *** tests typically consist of two to three crypto-crystal laminae,somewhat resembling bilamellar walls of *** tests consist of fine-grained particles agglutinated with siliceous cement,similar to agglutinated walls of *** Gaojiashan VSMs are broadly similar,at least in gross morphology,to the testate amoebae-like VSMs,but their relative large sizes(600-2400 μm) and possibly mineralized(rather than organic) tests argue against this *** also show some similarities to other protozoans,especially ***,tintinnids have robust pesudochitinous loricae consisting of both secreted and agglutinated ***,tintinnid loricae differ in shape from the Gaojiashan VSM tests in having a constricted aboral end(sometimes with a caudal appendix) and a flaring oral *** the Gaojiashan VSMs are indeed related to foraminifers,they indicate that foraminifers were important players in late Ediacaran communities.

关键词： Gaojiashan biota vase-shaped microfossils Foraminifera

Tetraradial symmetry in early poriferans

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Chinese Science Bulletin 2014年第7期59卷 639-644页

作者： Joseph P.Botting xunlai yuan Jih Pai Lin State Key Laboratory of Paleobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences

Here is currently little consensus on the branching order and phyletic status of the oldest metazoan groups, but sponges are widely believed to be the earliestbranching living metazoans. Porifera are thought to have diverged before the emergence of developmental characters typical of Eumetazoa, such as well-defined symmetry; extant sponges show radial symmetry of indeterminate high order, or none, combined with polarisation along the axis. In contrast, other early-branching phyla include bilateral and tetraradial(Cnidaria) and biradial(Ctenophora) symmetry, or none(Placozoa). A variety of prismatic early fossil sponges had shown here where the shared symmetry has been overlooked, and also describe structural tetraradial symmetry in Cambrian sponges from South China. Based on this study, this symmetry is likely to have been a primitive feature of sponges, and that the earliest-known fossil sponges were highly organised, cellularly integrated individuals whose body form was under strict genetic control.

关键词：对称性早期后生动物群多细胞动物多孔动物中国南方原始特征遗传控制

Rare earth elements and carbon isotope geochemistry of the Doushantuo Formation in South China:Implication for middle Ediacaran shallow marine redox conditions

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Chinese Science Bulletin 2012年第16期57卷 1998-2006页

作者： ZHOU ChuanMing JIANG ShaoYong XIAO ShuHai CHEN Zhe yuan xunlai State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of Sciences Nanjing 210008China State Key Laboratory for Mineral Deposits Research Department of Earth SciencesNanjing UniversityNanjing 210093China Department of Geosciences Virginia Polytechnic Institute and State UniversityBlacksburgVA 24061USA

The middle Ediacaran Shuram excursion, the largest negative δ 13 C carb excursion in Earth history, has been interpreted as indirect evidence for episodic oxidation and remineralization of deep ocean DOC (dissolved organic carbon). It has been hypothesized that such oxidation event may have occurred when anoxic DOC-laden deep water was brought to shallow shelves during oceanic upwelling, which is expected to cause localized anoxia in shallow environments. To test this prediction, we systematically analyzed rare earth elements (REE) and δ 13 C carb of the upper Doushantuo Formation carbonates in the Yangtze Gorges area of South China, which were deposited in an inner shelf environment and record a large negative δ 13 C carb excursion correlated to the Shuram event. The REE data show a significant positive shift in Ce/Ce* values, synchronous with a pronounced negative δ 13 C carb shift. This positive Ce/Ce* shift is interpreted to represent an oceanic anoxia event in shallow shelf environments, which may have been caused by the upwelling or impingement of oxygen-depleted and 12 C-enriched deep water onto shelves. This anoxia event coincides with a sharp decline in the abundance and diversity of Ediacaran acanthomorphic acritarchs, raising the possibility that these two geobiological events may be causally related.

关键词：海洋缺氧事件氧化还原条件同位素地球化学碳水化合物稀土元素陡山沱组中国南方迪卡

Anatomy and plant affinity of Chuaria

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Chinese Science Bulletin 2011年第12期56卷 1256-1261页

作者： WANG Xin yuan xunlai ZHOU ChuanMing DU KaiHe GONG Miao State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China College of Biological Sciences Nanjing Normal University Nanjing 210046 China Hunan Geological Museum Changsha 410007 China

Chuaria is one of the few globally distributed macrofossil pioneers documented in the Precambrian. It is perhaps the most controversial fossil in term of its affinity despite more than one hundred years of study. Many mutually exclusive affinities have been suggested for this frequently encountered fossil. Although often treated as a multicellular alga, this interpretation remains inconclusive because the lacking unambiguous demonstration of cellular structures. In this paper the cellular details of Chuaria are clearly revealed for the first time. The cell walls in Chuaria suggest that it is a multicellular eukaryotic alga, in agreement with the latest biogeochemical analyses. Different thicknesses of cell walls suggest primary cellular differentiation in this organism. Membrane-like structures within the cells (the first to be reported in Precambrian fossils) imply a eukaryotic nature. This study partially resolves the century-long controversy over the affinity of Chuaria, and makes Chuaria one of the few recognized multicellular eukaryotes before the Neoproterozoic glaciation.

关键词：亲和力解剖学真核生物植物细胞结构地球化学分析前寒武纪相互排斥