江西二叠—三叠系界线

本文描述了江西省北部、中部、南部地区二叠－三叠系界线剖面各１条,对每条剖面进行沉积相分析,从生物地层学角度论证其界线存在的可靠性,Ｈｉｎｄｅｏｄｕｓ ｐａｒｏｕｓ在江西修水清水岩乡东岭的发现是中国的又一新发现地区。二叠－三叠纪生物地层界线以Ｈ．ｐａｒｖｕｓ Ｍｏｒｐｈｏｔｙｐｅ１的首次出现为准;“界线粘土”层的底界属三叠－三叠系事件地层界线,与生物地层界线不是一回事,生物地层界线比事件地层界线在江     

二叠-三叠系界线层的牙形刺与生物地层界线

在研究二叠－三叠系界线地层时,应严格地将事件地层界线与生物地层界线区分开来。而定义生物地层界线时,也不应与“过渡层”或“混生层”的概念相连。在浙江长兴煤山,“界线粘土”层的底界,应为事件地层界线,界线层２的中部应为生物地层界线,比事件地层界线高１５ｃｍ。二叠－三叠系生物地层界线应以ＨｉｎｄｅｏｄｕｓｐａｒｏｕｓＭｏｒｐｈｏｔｙｐｅｌ的首次出现为准。在Ｈ．ｐａｒｖｕｓＭ．１缺乏的地区可以Ｃｌａｒｋｉｎａｃｈａｎｇｘｉｎｇｅｎｓｉｓ,Ｃ．ｄｅｆｌｅｃｔｓ,Ｃ．ｄｉｃｅｒｏｃａｒｉｎａｔａ,Ｃｌａｒｋｉｎａｓｐ．ｎｏｖ,Ｈｉｎｄｅｏｄｕｓｌａｔｉｄｅｎｔａｔｕｓ,Ｈ．ｔｙｐｉｃａｌｉｓ．Ｈ．ｃｈａｎｇｘｉｎｇｅｎｓｉｓｓｐ．ｎｏｖ等种的绝灭和ＨｉｎｄｅｏｄｕｓｐａｒｖｕｓＭ．２,Ｈ．ｔｕｒｇｉｄｕｓ,Ｏｐｈｉｃｅｒａｓ,Ｃｌａｒａｉａｗａｎｇｉ首次出现作为确定二叠－三叠系生物地层界线的辅助标准。这一生物地层界线恰在连续的单相地层中,完全符合全球界线层型剖面点的要求。因此长兴煤山忠心大队剖面是世界上最好的二叠－三叠系全球界线层型剖面点（ＧＳＳＰ）。     

二叠-三叠系界线层的牙形刺与生物地层界线

在研究二叠－三叠系界线地层时，应严格地将事件地层界线与生物地层界线区分开来。而定义生物地层界线时，也不应与“过渡层”或“混生层”的概念相连。在浙江长兴煤山，“界线粘土”层的底界，应为事件地层界线，界线层２的中部应为生物地层界线，比事件地层界线高１５ｃｍ。二叠－三叠系生物地层界线应以ＨｉｎｄｅｏｄｕｓｐａｒｏｕｓＭｏｒｐｈｏｔｙｐｅｌ的首次出现为准。在Ｈ．ｐａｒｖｕｓＭ．１缺乏的地区可以Ｃｌａｒｋｉｎａｃｈａｎｇｘｉｎｇｅｎｓｉｓ，Ｃ．ｄｅｆｌｅｃｔｓ，Ｃ．ｄｉｃｅｒｏｃａｒｉｎａｔａ，Ｃｌａｒｋｉｎａｓｐ．ｎｏｖ，Ｈｉｎｄｅｏｄｕｓｌａｔｉｄｅｎｔａｔｕｓ，Ｈ．ｔｙｐｉｃａｌｉｓ．Ｈ．ｃｈａｎｇｘｉｎｇｅｎｓｉｓｓｐ．ｎｏｖ等种的绝灭和ＨｉｎｄｅｏｄｕｓｐａｒｖｕｓＭ．２，Ｈ．ｔｕｒｇｉｄｕｓ，Ｏｐｈｉｃｅｒａｓ，Ｃｌａｒａｉａｗａｎｇｉ首次出现作为确定二叠－三叠系生物地层界线的辅助标准。这一生物地层界线恰在连续的单相地层中，完全符合全球界线层型剖面点的要求。因此长兴煤山忠心大队剖面是世界上最好的二叠－三叠系全球界线层型剖面点（ＧＳＳＰ）。     

江西二叠-三叠系界线层的牙形刺及Hindeodus-Isarcicela的演化谱系

对江西修水清水岩乡东岭剖面和乐平沿沟剖面的再研究表明,ＨｉｎｄｅｏｄｕｓｐａｒｖｕｓＭｏｒｐｈｏｔｙｐｅ１在东岭剖面首现于大冶组的最低层位,生物地层界线与岩石地层界线一致,仅比事件地层界线高５－６ｃｍ。沿沟剖面Ｈｉｎｄｅｏｄｕｓｐａｒｖｕｓ带厚仅３６ｃｍ,其首现与岩石地层界线也一致。张克信等提出的Ｈ．ｌａｔｉｄｅｎｔａｔｕｓ→Ｈ．ｐａｒｖｕｓ→Ｈ．ｔｕｒｇｉｄｕｓ→Ｉ．ｉｓａｒｃｉｃａ的演化谱系需作进一步修正。依据华南的资料,本文第一作者提出新的演化谱系：Ｈ．ｌａｔｉｄｅｎｔａｔｕｓ→Ｈ．ｐａｒｖｕｓ→Ｉ．ｓｔａｅｓｃｈｅｉ→Ｉ．ｉｓａｒｃｉｃａ。Ｈ．ｔｕｒｇｉｄｕｓ并不在此演化系列中,它属Ｈｉｎｄｅｏｄｕｓ的另一分枝。二叠三叠系界线层的牙形刺应区分出浮游相与浅水相。在浮游相,牙形刺序列为：（１）ＣｌａｒｋｉｎａｃｈａｎｇｘｉｎｇｅｎｓｉｓＣ．ｄｅｆｌｅｃｔａ带,（２）Ｃ．ｃａｒｉｎａｔａ带,（３）Ｃ．ｐｌａｎａｔａ带。在浅水相,牙形刺序列为：（１）Ｈ．ｌａｔｉｄｅｎｔａｔｕｓ带,（２）Ｈ．ｐａｒｖｕｓ带,（３）Ｉ．ｓｔａｅｓｃｈｅｉ带,（４）Ｉ．ｉｓａｒｃｉｃａ带,（５）Ｈ．ｐｏｓｔｐａｒｖｕｓ带     

江西二叠—三叠系界线层的牙形刺及Hindeodus—Isarcicella的演化谱系

对江西修水清水岩乡东岭剖面和乐平沿沟剖面的再研究表明,Ｈｉｎｄｅｏｄｕｓ ｐａｒｖｕｓ Ｍｏｒｐｈｏｔｙｐｅ１在东岭剖面首现于大冶组的最低层位,生物地层界线与岩石地层界线一致,仅比事件地层界线高５－６ｃｍ,沿沟剖面Ｈｉｎｄｅｏｄｕｓ ｐａｒｏｕｓ带厚仅３６ｃｍ,其首现与岩石地层界线与一致。张克信等提出的Ｈ。ｌａｔｉｄｅｎｔａｔｕｓ→Ｈ．ｐａｒｏｕｓ→Ｉ．ｉｓａｒｃｉｃａ的演化谱系需作进一步修正。依     

江苏丹徒大力山二叠—三叠系界线层的牙形刺

本文简要报道了江苏丹徒大力山二叠－三叠系界线层剖面中所产的丰富的牙形刺（计７属１３种及３个未定种）、腕足类、鱼鳞及鱼牙化石,讨论了二叠－三叠系生物地层界线的划分,并对牙形刺的３个未定种进行了描述,对江苏二叠－三叠系生物地层界线的划分具有重要意义。     

中国浙江长兴县煤山二叠—三叠系界线：三叠系底界的全球界线…

浙江长兴煤山剖面的二叠－三叠系界线层为连续的浮游相沉积没有任何间断,侧向上也是连续的。煤山是长兴阶的层型剖面所在地,长兴阶的上部,界线层和三叠系的下部,每一层都发现有牙形刺,可以逐层追索牙形刺的演化关系。煤山剖面几乎没有任何热力变质（ＣＡＩ＝１－１．５）。煤山剖面的菊石、牙形刺、双壳类、腕足类等多门类化石以及有关事件已得到了很好的研究。绝对年龄和古地磁也已得到深入研究。孢子的存在和易于识别的事件能     

浙江黄芝山剖面二叠-三叠系界线附近的牙形类序列及其地层对比

首次系统研究浙江黄芝山剖面二叠-三叠系界线附近的牙形类化石,共鉴定2属16种,并据此识别出5个牙形类化石带,从下至上依次为:Clarkina changxingensis changxingensis带,C.parasubcarinata带,C.chan-gxingensis yini-C.meishanensis zhangi带,C.meishanensis meishanensis带,Hindeodus parvus带。Hindeodus changxingensis,H.eurypyge,H.parvus分别在第15层、第18层底部、第18层中部依次出现,为确定该剖面二叠-三叠系界线在18-3层之底提供了依据。作者还讨论黄芝山剖面二叠-三叠系界线附近的牙形类序列与浙江煤山、伊朗剖面二叠-三叠系界线层牙形类序列的对比。     

浙江长兴二叠系-三叠系界线地层中的氨基酸

浙江长兴煤山剖面二叠系－三叠系（Ｐ／Ｔ）界线地层中的氨基酸分析结果显示，所研究样品中含有１６种生物来源的氨基酸，它们的总含量在Ｐ／Ｔ界线地层及下伏地层中的分布规律是：自下而上减少，这一趋势与正常海相地层中氨基酸含量随地层年代增加而减少的规律相反。Ｐ／Ｔ界线附近氨基酸总量上的异常变化趋势可能与二叠纪末生物绝灭事件有关，即由于二叠纪末所在海域重托叫量的急剧减少所致。此外，检测了被认为是地外氨基酸的α－     

浙江和江西二叠/三叠系界线以下的软骨鱼类微体化石——华南二叠/三叠系界线上下鱼类序列研究之五

记述了浙江长兴县煤山剖面、江西修水县四都乡东岭剖面和信丰县铁石口镇铁石口剖面二叠/三叠系界线以下的软骨鱼类10个类别的微体化石,包含5科6属5种,其中有3新属5新种,它们是:刘氏煤山鲨(Meishanselache liuigen.et sp.nov.)、王氏长兴鲨(Changxingsela-che wangigen.et sp.nov.)、东岭中华尖齿鲨(Sinacrodus donglingensis gen.et sp.nov.)、修水滑齿鲨(Lissodus xiushuiensis sp.nov.)和江西多尖齿鲨(Polyacrodus jiangxiensis sp.nov.)。浙、赣两省的这批软骨鱼类微体化石显示两个特点:组成以弓鲛超科化石为主;发现于特提斯区三叠纪的鲨类与发现于中国南方晚二叠世的鲨类具有密切的亲缘关系。这是包含全球二叠/三叠系界线层型剖面和点位(GSSP)在内的全球二叠/三叠系界线以下软骨鱼类微体化石序列的首次报道。软骨鱼类是我国鱼类化石研究中最为薄弱的一个环节,本文化石的记述大大地填补了这个薄弱环节。     

泥盆纪最早期和最晚期珊瑚群研究的进展——兼论泥盆纪珊瑚的绝灭、复苏及其底栖组合

由于志留泥盆纪之间没有发生明显的生物更替现象,所以泥盆纪最早期（Ｌｏｃｈｋｏｖｉａｎ）的珊瑚仍保留着浓厚的志留纪珊瑚的色彩。真正的泥盆纪类型的珊瑚是从早泥盆世中期（Ｐｒａｇｉａｎ）才开始兴起的,至晚泥盆世早期（Ｆｒａｓｎｉａｎ）末惨遭绝灭。晚泥盆世晚期（Ｆａｍｅｎｎｉａｎ）的珊瑚却与石炭纪珊瑚有着较为密切的关系。晚泥盆世的珊瑚经历了绝灭残存复苏３个发展阶段。泥盆石炭纪之交,泥盆纪最晚期（Ｓｔｒｕｎｉａｎ）的珊瑚再遭绝灭,至石炭纪初代之于Ｔｏｕｒｎａｉｓｉａｎ型的珊瑚。正当华南锡矿山（相当于Ｆａｍｅｎｎｉａｎ早期）的珊瑚群罹难的时刻,新疆北部洪古勒楞（亦相当于Ｆａｍｅｎｎｉａｎ早期）却形成了Ｆ／Ｆ大绝灭后生物理想的避难所。     

浙江和江西二叠/三叠系界线层上下的辐鳍鱼类化石与鱼类的绝灭、复苏和辐射

记述了浙江长兴县煤山剖面、江西修水县四都乡东岭剖面和信丰县铁石口镇铁石口剖面二叠/三叠系界线层上下的辐鳍鱼类6个类别的微体化石,包含2新属2新种,它们是:赵氏浙江鱼(Zhejiangichthys zhaoi gen.et sp.nov.)和小齿葆青鱼(Baoqingichthys microdontus gen.et sp.nov.)。这是包括全球二叠/三叠系界线层型剖面和点位(GSSP)在内的全球二叠/三叠系界线层上下辐鳍鱼类微体化石序列的首次报道。在总结煤山剖面已记述的鱼类大化石和微体化石资料的基础上,分析了长兴煤山剖面二叠纪末鱼类的集群绝灭。绝灭发生得很晚,持续的时间很短,规模也很大,绝灭率高达93%。讨论了华南二叠/三叠系之交大绝灭后鱼类的复苏和辐射,认为鱼类和牙形类一样都是大绝灭后在三叠纪最早复苏的类别,最早复苏的鱼类为裂齿鱼类;鱼类从绝灭期到辐射期仅用了1.3 Ma到4 Ma,从地质时间考虑,大绝灭后鱼类的复苏和辐射是相当快的。华南早三叠世以裂齿鱼类的张氏鱼(Zhangina)和软骨鱼类的弓鲛(Hybodus)为代表的组合替代了晚二叠世以古鳕类的中华扁体鱼(sinoplatysomys)和软骨鱼类的中华尖齿鲨(Sinacrodus)为代表的组合。华南晚二叠世海相地层产出的辐鳍鱼类和软骨鱼类的一些土著属与产于特提斯区三叠纪的一些属非常相近,表明华南下扬子区很可能是后来繁盛于特提斯区的三叠纪鱼类的发源地。     

Thecamoebians (Testate Amoebae) Straddling the Permian-Triassic Boundary in the Guryul Ravine Section,India: Evolutionary and Palaeoecological Implications

Exceptionally well-preserved organic remains of thecamoebians (testate amoebae) were preserved in marine sediments that straddle the greatest extinction event in the Phanerozoic: the Permian-Triassic Boundary. Outcrops from the Late Permian Zewan Formation and the Early Triassic Khunamuh Formation are represented by a complete sedimentary sequence at the Guryul Ravine Section in Kashmir, India, which is an archetypal Permian-Triassic boundary sequence [1]. Previous biostratigraphic analysis provides chronological control for the section, and a perspective of faunal turnover in the brachiopods, ammonoids, bivalves, conodonts, gastropods and foraminifera. Thecamoebians were concentrated from bulk sediments using palynological procedures, which isolated the organic constituents of preserved thecamoebian tests. The recovered individuals demonstrate exceptional similarity to the modern thecamoebian families Centropyxidae, Arcellidae, Hyalospheniidae and Trigonopyxidae, however, the vast majority belong to the Centropyxidae. This study further confirms the morphologic stability of the thecamoebian lineages through the Phanerozoic, and most importantly, their apparent little response to an infamous biological crisis in Earth’s history.     

On the faunal verification of the Permo-Triassic boundary in continental deposits of eastern Europe: 1. Gorokhovets-Zhukov ravine

A reference section of the Permian and Triassic continental deposits of the Zhukov ravine near the town of Gorokhovets (Vladimir Region) is described and new tetrapod localities are characterized. The position of the Permian-Triassic boundary in this section is recognized and its faunal substantiation based on vertebrates is provided for the first time. The Zhukov ravine section is unique in the fact that it shows a thick stratigraphically continuous succession of the Permo-Triassic boundary beds, with three successive tetrapod zones: the terminal Permian Chroniosuchus paradoxus and Archosaurus rossicus zones and the Early Triassic Tupilakosaurus wetlugensis Zone.     

中国当阳跑马岗组白垩-古近系界线附近的轮藻组合

陆相白垩-古近系过渡段的生物地层记录通常稀少而不连续。从轮藻角度讲,中国当阳跑马岗组的白垩-古近系过渡段的生物地层记录是世界上迄今所知的最连续和最丰富的。该过渡段剖面的介形类也非常丰富,其它建立界线辅助层型所需的许多条件也很好,或许当阳跑马岗组剖面可作为白垩-古近系界线陆相辅助层型的候选剖面。对该剖面白垩-古近系界线附近的轮藻组合作了简要的介绍。     

The rodent succession in the Sifón de Librilla section (Fortuna Basin,SE Spain): implications for the Mio-Pliocene boundary in the Mediterranean terrestrial record

The long and continuous continental section of Sifón de Librilla (Fortuna Basin, southern Spain) provides a detailed biostratigraphic record distributed along eight localities, in which the magnetostratigraphy has been unambiguously established. This section therefore provides a unique opportunity to cross biostratigraphic information with magnetostratigraphic data to establish a reliable frame to date sites. This 800-m-thick sequence extends from the latest Miocene to the early Pliocene, recording more than 2 Myr. Here we provide a complete taxonomic survey of the recovered rodent remains, defining a new cricetid species named as Hispanomys romeroi. We also refine the phylogenetic relationships of the Apodemus, Stephanomys, Paraethomys, Ruscinomys and Apocricetus lineages. Considering the accurate age of the associations, we discuss the chronology of the first and last appearances of some species. In addition, this section clearly records the Mio-Pliocene boundary, allowing us to correlate between the marine and continental biostratigraphic scales. Taking advantage of this opportunity, we explore key biostratigraphic indicators for identifying the beginning of the Pliocene in the continental records, as well as for differentiating the MN13 and MN14 units, most specially the FOD of Occitanomys brailloni. According to this datum, we conclude that the Miocene-Pliocene boundary coincides with that of MN13-MN14 units. http://www.zoobank.org/urn:lsid:zoobank.org:act:BDA60E97-C23B-482D-AD0D-9C25FDF5FA05     

Integrated magnetobiochronology of the Early/Middle Eocene transition at Agost (Spain): Implications for defining the Ypresian/Lutetian boundary stratotype

In this paper, we present an integrated study of a 115‐m‐thick section that spans the Ypresian/Lutetian boundary at Agost (Betic Cordillera, SE Spain). Our study includes magnetostratigraphic results and biostratigraphic and palaeoenvironmental data derived from planktic foraminifera, small and larger benthic foraminifera, and calcareous nannofossils. Our results demonstrate that the Agost section is continuous and spans from Zones P9 to P12 (E7 to E10), Zones CP11 to CP14a (NP13 to NP16), Zones SBZ11 to SBZ15, and Chrons C22n to C19r. The first occurrence (FO) of H. nuttalli (base of P10) and the FO of G. nuttalli (base of E8) are found within Chron C20r, at a much younger age (3–5 Myr) than previously considered in standard calibration schemes. Similarly, the boundary between SBZ12 and SBZ13 is located within Chron C21n, also at a younger age than previously considered. On the contrary, the FO of B. inflatus (base of CP12b) is found within Chron C21r, which conforms to the magnetostratigraphically calibrated age of ca. 48 Ma (middle part of C21r) considered in standard calibration schemes. These results corroborate earlier studies and indicate that all the events that have been proposed to mark the Ypresian/Lutetian boundary appear at different stratigraphic intervals and have different ages. Based on our results from Agost and on data from other sections elsewhere, we suggest that the Ypresian/Lutetian boundary might be approximated by the FO of B. inflatus (base of CP12b). The Agost section might be considered as a potential candidate to locate the Global Stratotype Section and Point (GSSP) of the base of the Lutetian Stage, because it includes all the events that might be selected as marker events for the Ypresian/Lutetian boundary and it fulfils most of the geological, biostratigraphic and infrastructure requirements demanded for definition of a GSSP.     

湖南慈利康家坪剖面二叠纪末类有孔虫的灭绝过程

湖南慈利地区二叠系-三叠系界线附近地层非常发育,是探讨二叠纪-三叠纪之交生态系转变的良好区域。本研究通过对该地区康家坪剖面长兴组上部与大冶组下部地层进行系统采样、切片研究,在长兴组上部地层中发现278个类有孔虫,共鉴定出4属11种(含2个未定种)。这些类有孔虫在地层中的分布表明类有孔虫在二叠纪末经历了一次突变式的灭绝过程,其灭绝层位位于长兴组顶部的生物碎屑灰岩与大冶组底部的微生物岩之交界线处。该研究不仅丰富了康家坪剖面在这一关键时期的生物群面貌,而且也为二叠纪末的生物灭绝事件的深入研究提供了新的材料。