高于庄古生物学

距今14～16亿年的华北地区高于庄组黑色层状、结核状和透镜状燧石与叠层石的黑色硅质部分中保存着极丰富的原核和真核生物微化石。宏观藻类在该组的页岩中亦已发现,本组为评估中元古代生命状况,古环境和显生宙生物地层提供了重要的生物信息。迄今为止在高于庄组地层中已有百余个化石种被人们认识,根据古植物和古环境的特征这些生物种类可分为三个不同的组合,即：1.颤藻和色球藻组合,出现在高于庄组一段,代表浅水藻席建造和居住与一些可能的外来浮游生物的种类;2.念珠藻组合,仅发生在该组的二段,还含一些底栖藻席建造或居住的种类;3.第四段的色球藻组合,它代表了潮间带至亚潮带的藻席建造和外来的种类。元古代燧石中的微化石,尤其是蓝藻化石,尽管在元古代它们就已不断趋向于多样化,但由于它们形态上的保守性,对环境的指示比对地质时代的指示更有价值。高于庄组微化石的特点和大多数链状念珠藻垂直层理保存的事实表明：1.高于庄组藻化石的个体大小随时间趋向于增大;2.高于庄组的沉积可能是处于一个淡水环境,且沉积率可能等于或少于微生物的生长率;3.高于庄组织沉积模式可能是多潮间带至亚潮带或深海,然后再至潮间带或潮上带;4.当高于庄组沉积时真核生物亦已出现。     

高于庄古生物学

距今14～16亿年的华北地区高于庄组黑色层状、结核状和透镜状燧石与叠层石的黑色硅质部分中保存着极丰富的原核和真核生物微化石.宏观藻类在该组的页岩中亦已发现.本组为评估中元古代生命状况、古环境和前显生宙生物地层提供了重要的生物信息.迄今为止在高于庄组地层中已有百余个化石种被人们认识.根据古植物和古环境的特征这些生物种类可分为三个不同的组合,即:1.颤藻和色球藻组合,出现在高于庄组一段,代表浅水藻席建造者和居住者与一些可能的外来浮游生物的种类;2.念珠藻组合,仅发生在该组的二段,还含一些底栖藻席建造者或居住者的种类;3.第四段的色球藻组合,它代表了潮间带至亚潮带的藻席建造者和外来的种类.元古代燧石中的微化石,尤其是蓝藻化石,尽管在元古代它们就已不断趋向于多样化,但由于它们形态上的保守性,对环境的指示比对地质时代的指示更有价值.高于庄组微化石的特点和大多数链状念珠藻垂直层理保存的事实表明:1.高于庄组微化石的个体大小随时间趋向于增大;2.高于庄组的沉积可能是处于一个淡水环境,且沉积率可能等于或少于微生物的生长率;3. 高于庄组织沉积模式可能是从潮间带至亚潮带或深海,然后再至潮间带或潮上带;4.当高于庄组沉积时真核生物亦已出现.     

华北高于庄组硅化微体化石组合的古环境

华北中元古代高于庄组 ( 1 4- 1 5亿年 )的硅质叠层石中保存了完好的多种微生物化石。从这些叠层石的微细构造分析 ,成岩早期硅质矿物的交代作用为微体化石的原位保存起了很重要的作用。除部分居住者和浮游的分子外 ,两种丝状蓝藻 ( Siphonophycus inornatum和Eoschizothric composita)和两种球状蓝藻 ( Coccostratusdispergens和 Eoentophysalisbelcherensis)是这些藻席的主要建造者。以球状蓝藻 Eoentophysalis为主的藻席可能发育于潮下高能环境中 ;而以多种丝状蓝藻为主的藻席可能反映了当时的沉积环境为中—高潮间带的局部静止小水体     

天津蓟县中元古界高于庄组宏观化石的发现及其地质意义

在蓟县长城系高于庄组(1500—1400Ma)中部的泥质含灰质白云岩中发现可靠的宏观化石,代表分子包括Parachuaria,Parashouhsienia,Grypania和Spirelluchnum等属。研究表明,宏观化石形成于浪基面以下海水能量低的陆表海台盆区。围岩环境为台盆相弱还原静水环境;燕山地区的高于庄组与美国蒙大拿州中元古代贝尔特超群下部的Greyson页岩地层可以对比;遗迹化石如果被确认,可表明1450Ma年前后已经存在一种结构简单、不分叉,具两侧对称的长形体型,有前后端之分的似蠕虫活动能力的早期后生动物;长城系(1800—1400Ma)不仅是后生植物出现和繁盛的重要阶段也可能是后生动物出现和发展的关键时期。     

华北太行山北段高于庄组微古植物的新发现

长城群高于庄组主要分布于我国华北地区,地质年龄约在14－16亿年。主要描述了华北太行山北段灵邱县境内高于组白云岩中的层状和扁豆状透镜体燧石及穹隆式叠层石的黑色燧石中的颤藻、念珠藻和色球藻植物的8个新种和3个未定种,其中还有两个新修订属。这些新的促群再加上前人在高于庄组地层中已报道的汇成了近100个种生物组合,进一步证明高于庄组地地球上中元代微化石类群最丰富的产地之一。以下是该 新发现和新修订的分类类群：颤藻科（Oscillatoriaceae): Eophormkidium orculiformis sp. nov., E. sp., Siphonophycus caudataceous sp. nov., Palaeolyngbya complanata sp. nov., P. capitata sp. nvo., P. sp., Oscilaltoriopsis sp.;念珠藻科（Nosto-caceae):Veteronostiocale vaginata sp.nov.;色球藻科（Chroococcaceae):Maculosphaera giganta sp.nov.,Gloeotheceopsis grandis sp.nov.;分类位置未定的类群：Myxococcoides limpida sp.nov.。     

认识古生物学

时光如流水,日历一页页翻过,随手或者刻意留下的备忘录一页页被压在下面,越早发生的事,被压在了越下面。当我们总结工作或者整理心情的时候,翻阅日历看到写下的潦草字迹,就会回忆起当时的情形,甚至感同身受,如临当日。翻阅备忘录,翻阅自己的历史,日历记载着我们逝去的年华与心情。地层,就是地球的日历,记载着曾     

特征形状分析方法在古生物学研究中的应用

一、前言1983年,美国古生物学家G. P. Lohmann发明了“特征形状分析”(eigenshape analysis)方法,用其分析、对比浮游有孔虫不同居群的形态,并取得了良好的结果(Lohmann, 1983;Malmgren, Berggen and Lohmann, 1984)。采用这种分析方法,可以从一个物种的一批标本中计算、重建出一批“特征形状”(eigenshape)来代表这批标本(或一个居群)的形状特征。通过对不同居群的“第一特征形状”(first eigenshape)的对比,可以发现不同居群的生物个体在形状上的主要差异。但是,运用这种方法来研究不同居群间的形态差异时,必须借助文字来描述它们的特征形状之间的差异,且无法定量地表示出,这些差异的大小,这就给进一步分析、利用形态对比的结果带来了困难.针对这一缺陷,笔者和S.M.Stanley在研究北美新第三纪海相双壳类的演化模式的过程中,提出了用“不重合面积百分比”(percentage of     

一位古生物学家的遗迹--杨式溥教授(1925-2002)对地质学和古生物学的贡献

回顾和总结了杨式溥教授一生为中国地质学和古生物学所做出的重要贡献。以其公开发表的论著为基础,论述了杨式溥在中国石炭纪地层学、腕足动物化石、古遗迹学以及古生态学等研究领域的贡献,并简要评述了他的学术思路和治学特色。杨式溥对中国西北和西南地区石炭纪的腕足动物化石的研究为中国石炭纪地层的内部界线划分、对比、化石组合、地理区系及沉积类型提供了重要证据。杨式溥是中国古生态学和古遗迹学的奠基人,他全面系统地引入了古生态学的概念与方法,并在全国高校首次开设了有关课程。他对中国各时代、不同沉积相中的遗迹化石的系统描述和遗迹相的研究开拓了中国古生物学的新领域。杨式溥执教半个多世纪,为中国地质和古生物事业培养了大批专门人才。文后附有以出版年代为序的杨式溥所著文献的完整目录。     

浅谈大数据语境下的古生物学研究*

近半个世纪以来, 基于数据的古生物学研究日益占据重要位置。当下的科学研究进入大数据时代已得到公认, 虽然囿于总体上非实验性学科的特点, 古生物学数据产出速度有限, 目前尚难符合大数据的多数基本特征, 但大数据时代及相关理念显然对古生物学研究产生了积极效应, 比如近年来古生物学数据产出的多元化, 数学方法与模型的复杂化均与之密不可分。本文主要基于作者研究经验, 浅议了古生物学定量化研究历史三个阶段, 同时考虑古生物不同门类数据的相通性, 在大数据语境下将古生物学数据分为结构型、半结构型与非结构型, 并简介了基本研究方法。在讨论了定量古生物学与分析古生物学两大研究视角的异同后, 基于古生物学代表期刊最新论文的小样本抽样, 本文强调了分析古生物学的研究思路与统计模型较传统统计方法的优势。近年来古生物学展示了数据驱动型研究的特点, 未来可能需要同时重视模型驱动的研究视角, 将自上而下问题导向的模型设计与自下而上基于数据的收集分析相结合, 以保证古生物学数据研究的可持续发展。此外, 古生物学不是数据密集型科学, 未来将之与地学其他领域的数据有机整合, 会促成古生物学在学科交叉方向的深入。最后, 统计学领域最新的倡议同样需要古生物学者重视, 对统计模型的选择与对数据的解读需要考虑系统的复杂性与多解性, 统计显著性相关的因果规律识别尤其需要慎重。     

世界著名的地质学家,中国微体古生物学创始人李四光──纪念李四光教授诞辰105周年

世界著名的地质学家，中国微体古生物学创始人李四光──纪念李四光教授诞辰１０５周年原中国科学院古生物研究所副所长李扬今年１０月２６日是李四光诞辰１０５周年，也是他兼中国科学院古生物研究所首任所长４４周年。李四光对地学的杰出贡献是多方面的：创建了中国微体...     

New Microorganisms from the Gaoyuzhuang Formation of Northern Taihang Mountains,China

A new diverse assemblage of microorganisms has been discovered in black bedded, nodular and lenticular cherts and dark chert of domical stromatolites in dolostone of the Gaoyuzhuang Formation in Lingqiu County, northern Taihang Mountains. The geologic relationships, biostratigraphic correlations, and available radiometric age determinations place the age of the Gaoyuzhuang Formation at approximately 1 400-1 600 million years in age. Eight new species, three unnamed species, and two emended genera of oscillatoriacean, nostocacean, and chroococcacean cyanobacteria are described. These data coupled with reports of others indicate that the diversity of taxa in the Gaoyuzhuang Formation reaches 100 species. The Gaoyuzhuang Formation contains one of the richest Mesoproterozoic communities of microfossils. The following new and emended taxa are described: Oscillatoriaceae: Eophormidium orculiformis sp. nov., E . sp., Siphonophycus caudataceous sp. nov., Palaeolyngbya complanata sp. nov., P. capitata sp. nov., P . sp. and Oscillatoriopsis sp..Nostocaceae: Veteronostocale vaginata sp. nov.. Chroococcaceae: Maculosphaera giganta sp. nov. and Gloeotheceopsis grandis sp. nov. Incertae sedis: Myxococcoides limpida sp. nov.     

Investigation on the Procaryotic Microfossils from the Gaoyuzhuang Formation,Jixian, North China

Stromatolitic cherts of the late Precambrian Gaoyuzhuang Formation at the Stratotype section of the “Sinian Suberathem” near Jixian, North China, contain a varied assemblage of well-preserved filamentous and coccoid blue-green algae. This assemblage constitutes perhaps one of the well-preserved, diverse Precambrian microbiota now known. The fossiliferous cherts occur in the lower part of this formation which is about 1500 Ma-old interpolated depending on Pb-Pb ages yielded from the middle part of it and K-Ar ages yielded from the underlying Dahongyu Formation. Fifteen new taxa of microfossils, comprising 6 new genera, are here described from the Gaoyuzhuang stromatolitic cherts. All species of blue-green algae have been recognized in the assemblage and refer to the modern Chroococcaceae, OsciUatoriaceae, Nostocaceae and Rivullariaceae. Most of these fossil algae are comparable in morphological details particularly to living Cyanophyta. It is evident that the cyanophytes had become well-diversified already by the late Precambrian. This evidence indicates that at least the morphological details are similar to those exhibited in living cyanophytes and these blue-green algae have not changed since Gaoyuzhuang time. This apparent evolutionary conservatism is probably attributable to a wide ecological tolerance and flexibility and also reflects its inherent genetic stability. The plant phylogenesis especially of Cyanophyta is discussed in this paper according to microfossil records detected in the thin sections of stromatolitic cherts from the Gaoyuzhuang Formation. Based on morphological characteristics and their generations Rivullariaceae may originate from Oscillatoriaceae. In addition algal biocoenoses in this stromatolitic chert grew in the form of laminar mats in the apparently subtital to intertital environment. The paleoclimate was subtropical or tropical. The following new taxa are here described:Microcystopsis yaoi, Eoaphanothece zhuiana, Oscillatoriopsis acuminata, O. hemisphaerica, O. disciformis, O. glabra, O. tuberculata, Eophormidium liangii, E. capitatum, E. semicirculare, Schizothropsis caudata, Paleoisocystis monosporata, P. disporata, Anabaenidium sophoroides and Paleocalothrix xui.     

A New Frontier for Palaeobiology: Earth's Vast Deep Biosphere

Diverse micro‐organisms populate a global deep biosphere hosted by rocks and sediments beneath land and sea, containing more biomass than any other biome except forests. This paper reviews an emerging palaeobiological archive of these dark habitats: microfossils preserved in ancient pores and fractures in the crust. This archive, seemingly dominated by mineralized filaments (although rods and coccoids are also reported), is presently far too sparsely sampled and poorly understood to reveal trends in the abundance, distribution, or diversity of deep life through time. New research is called for to establish the nature and extent of the fossil record of Earth's deep biosphere by combining systematic exploration, rigorous microanalysis, and experimental studies of both microbial preservation and the formation of abiotic pseudofossils within the crust. It is concluded that the fossil record of Earth's largest microbial habitat may still have much to tell us about the history of life, the evolution of biogeochemical cycles, and the search for life on Mars.     

13亿年前叠层石的生长节律和地-日-月动力学

研究的微小型叠层石Pseudogymnosolen f．产于华北蓟县中元古代蓟县系雾迷山组,年龄近1300Ma。该种叠层石具有非常清楚的生长节律,而且由小到大至少可划分出三个的级别,即“基本层”、“基本层组”和“叠层石带”,它们分别被解释为昼夜节律、月节律和年节律。根据月节律中的昼夜节律数和年节律中的月节律数,得出的初步结论是在近1300Ma以前,古月球绕古地球旋转1周至少需要42天,古地球绕古太阳公转一周,古地球至少要自转546周,古月球绕古地球至少要旋转13周,古地球自转1周最多仅需16．05小时。     

Multi-trichomous cyanobacterial microfossils from the Mesoproterozoic Gaoyuzhuang Formation, China: Paleoecological and taxonomic implications

Populations of the multi-trichomous microbial fossil Eoschizothrix composita n.gen. et sp. are preserved in growth position in silicified stratiform stromatolites of the Gaoyuzhuang Formation, Hebei Province, northern China. The microbial fossils consist predominantly of preserved sheaths, although several specimens retain shriveled remains of trichomes within sheaths. Comparisons with modern morphological counterparts, including shape, growth habit and orientation, degradational sequences, and habitat, support the interpretation of the multi-trichomous microfossils as cyanobacteria, which acted as frame-builders of ancient stromatolites. The distribution and orientation of multi-trichomous microfossils within a synsedimentary context reveal their behavioral responses to sedimentation regime. Horizontally spread, interwoven mats formed during periods of sedimentary stasis. During periods of rapid sediment influx, the filaments assumed an upright orientation, possibly to avoid accumulating particles. This is the first record of fossil stromatolite-building multi-trichomous cyanobacterial which underscores early morphological and functional diversification in cyanobacterial evolution.