首页科研进展
  • 福建漳浦发现中新世木乃伊化橄榄果核
    近期,中国科学院南京地质古生物研究所博士研究生尹素心在研究员史恭乐指导下,研究了东南沿海福建漳浦中中新世佛昙群发现的大量三维立体、木乃伊化保存的橄榄果核(图1)。研究成果近期发表于《远古世界》(Palaeoworld)。橄榄又名青榄、青果,是我国南方特有的一种水果。橄榄树在我国也有着悠久的栽培历史,古文献记载,汉代时橄榄树就已经被普遍种植。不同于压榨橄榄油所用的木犀科木犀榄属的油橄榄树,我国南方的橄榄树属于橄榄科橄榄属。橄榄树可作为行道树,木材可用于制作家具。橄榄果实作为人类的食物有着悠久的历史,最早甚至可以追溯到中石器时代。果实营养丰富,可食用,也可入药。橄榄果核是传统工艺微雕的材料之一,橄榄核雕又被称为榄雕。近期,中国科学院南京地质古生物研究所博士研究生尹素心在研究员史恭乐指导下,研究了东南沿海福建漳浦中中新世佛昙群发现的大量三维立体、木乃伊化保存的橄榄果核(图1)。研究成果近期发表于《远古世界》(Palaeoworld)。研究团队利用显微CT(图2)和扫描电子显微镜技术详细研究了这些化石材料。通过形态对比发现漳浦中中新世的橄榄果核不同于目前橄榄属的所有现生种和化石种,因此将其命名为一新种——浩敏橄榄Canarium haominiae sp. nov.。该种名用以纪念已故的李浩敏老师对我国新生代古植物研究的贡献。橄榄科是现代亚洲热带雨林和季雨林的优势类群之一。橄榄果核化石的发现进一步证实了漳浦生物群是一个中中新世热带季雨林生态系统,同时也表明了橄榄属自中中新世以来可能一直都是亚洲热带森林的重要组分。研究得到了中国科学院战略先导专项(B)、国家自然科学基金和中国科学院青促会的联合资助。论文信息:Yin Su-Xin, Wu Xie-Ting, Wang Zi-Xi, Shi Gong-Le*, in press. First fossil record of Canarium (Burseraceae) from the middle Miocene of Fujian, Southeastern China and its paleoecological implications. Palaeoworld, https://doi.org/10.1016/j.palwor.2022.03.009.图1. 福建漳浦中中新世浩敏橄榄图2. 福建漳浦中中新世浩敏橄榄显微CT数据三维重建
    2023-09-19
  • 叶脉特征和角质层结构揭示裸子植物化石系统学与演化新认识
    相关研究为更好理解古植物演化特征和生态适应性提供了重要线索,同时也突出了叶脉结构和角质层构造的对比研究在古植物学科发展中的重要性。相关成果发表在国际学术刊物《古植物与孢粉学论评》(Review of Palaeobotany and Palynology)。
      植物化石的叶脉特征和角质层结构在系统分类研究中发挥重要作用,也是属种鉴定的重要依据。然而由于植物化石常常保存不完整,导致诸多植物类群因极其相似的叶形或叶脉结构无法实现准确的类群划分。
      近期,中国科学院南京地质古生物研究所博士生许媛媛,在研究员王永栋及瑞典自然历史博物馆教授Stephen McLoughlin的共同指导下,对古生代和中生代常见的三个形态相似植物化石类群开展了叶脉结构及表皮特征的深入对比研究,为全面了解这些类群的系统分类和演化历史提供了新的认识。相关研究为更好理解古植物演化特征和生态适应性提供了重要线索,同时也突出了叶脉结构和角质层构造的对比研究在古植物学科发展中的重要性。相关成果发表在国际学术刊物《古植物与孢粉学论评》(Review of Palaeobotany and Palynology)。
      研究人员选取不同地史时期的三个特征分类群,包括:舌羊齿属(Glossopteris,二叠纪特征类群)、渔网叶属(Sagenopteris,中生代代表类群)和大网羽叶属(Anthrophyopsis,晚三叠世特征类群)开展比较研究。这三个属的叶片均具有典型的网状叶脉结构,叶形态也十分相似,化石如果为碎片或保存不佳时,常会导致属种难以区分或者鉴定错乱。
      之前的研究认为,舌羊齿类、开通目(渔网叶属)和本内苏铁目(大网羽叶属)在系统发育分析结果中位置相近,且均与早期被子植物密切相关。它们所具备的典型网状叶脉结构最早可以追溯到约三亿年前的宾夕法尼亚期(图1)。
      研究人员使用植物叶片的叶脉交叉类型和气孔特征,对舌羊齿、渔网叶和大网羽叶三个属的叶脉模式和气孔结构开展标准化的描述和对比(图2)。通过叶片宏观和微观形态的重新分析,揭示出它们之间存在的重要差异,这非常有助于区分化石类群,尤其对那些保存不完整的标本十分有效。
      通过进一步的研究表明,它们的叶脉连结方式独特且角质层显示出不同的气孔发育特征,即舌羊齿具有周缘型和单环型气孔组合;渔网叶属具有短而消散的中脉和不规则型气孔,副卫细胞不显著;而大网羽叶属叶片具有独特的叶脉交叉联结方式以及与本内苏铁植物一致的平列型气孔(图3)。
      尽管许多的植物类群在形态上表现出极大的相似性,但它们在进化历史上的位置可能并不相关。相似的植物叶脉结构更可能是趋同演化的结果,难以作为不同类群之间亲缘关系远近的佐证。与舌羊齿属、渔网叶属和大网羽叶属十分相似的网状叶脉植物,也在许多其他类群中独立出现,这种特征也可以表现出生态或生理上及演化方面的趋同性。据此对此前部分学者提出的舌羊齿类、开通目和本内苏铁目亲缘关系密切的观点提出新的看法。
      本研究得到了国家自然科学基金项目、中国科学院战略先导B类项目、现代古生物学和地层学国家重点实验室基础和自主项目、瑞典研究理事会和国家留学基金委联合资助。
      论文相关信息:Yuanyuan Xu, Yongdong Wang*, Stephen McLoughlin*, 2023.How similar are the venation and cuticular characters of Glossopteris, Sagenopteris and Anthrophyopsis. Review of Palaeobotany and Palynology, 316, 104934. . https://doi.org/10.1016/j.revpalbo.2023.104934.
      图1. 地质历史时期几种代表性网状脉植物类群的时代分布.
      图2. 舌羊齿属(A–D)、渔网叶属(E–G)和大网羽叶属(H–J)的叶片形态和网状脉连接特征. 
      Scale bars for A, C, E, G, H–J = 10 mm, for B, D, F = 5mm.
      图3. 舌羊齿属(A–G)、渔网叶属(H–J)和大网羽叶属(K–P)角质层微细构造特征. 
      Scale bars for A–D, N = 100 μm, for E–G = 10 μm, for H = 100 μm, for I = 300 μm, for J, K–L = 50 μm, for J, M, O = 30 μm, P = 20 μm.
    2023-09-14
  • 晚古生代大冰期碱湖烃源岩多阶段接力生油机制取得新认识
    科研人员以晚古生代大冰期准噶尔盆地发育的碱湖烃源岩是否具有多阶段生油模式为科学问题,通过高分辨率傅里叶变换回旋共振质谱(FT-ICR MS)技术从杂环化合物角度开展研究。相关研究成果发表于《有机地球化学》(Organic Geochemistry)期刊上。
      晚古生代大冰期全球发育多套富有机质沉积,是重要的碳汇,记录了生物-环境协同演化、碳循环与油气资源形成,是当前地球系统科学研究和石油地质学交叉前沿研究的一个重要方向。
      准噶尔盆地二叠系发育全球迄今发现最古老的碱湖烃源岩,是重要的科学研究对象。最近,中国科学院南京地质古生物研究所助理研究员张景坤,南京大学教授曹剑,以及中国石油新疆油田公司等同行合作,以晚古生代大冰期准噶尔盆地发育的碱湖烃源岩是否具有多阶段生油模式为科学问题,通过高分辨率傅里叶变换回旋共振质谱(FT-ICR MS)技术从杂环化合物角度开展研究。相关研究成果发表于《有机地球化学》(Organic Geochemistry)期刊上。
      研究通过重建含氮杂环化合物结构演变过程,揭示了有机质热演化的分子指纹记录。受检测技术的限制,分子量偏大的杂环类化合物是油气地球化学研究的薄弱环节,科学意义未充分揭示。本项工作借助新兴的FT-ICR MS技术,在准噶尔盆地下二叠统风城组碱湖相的有机质中最多检出2541种杂环化合物,并主要以Ny和NyOx化合物为主。通过精细对比烃源岩与原油中的含氮化合物组成,基于无荧光叶绿素代谢物(NCCs)演化模型,重建了烃源岩有机质经热裂解、脱氧与再聚合等作用最终转化为Ny和NyOx化合物的分子演化过程(图1),进而揭示了有机质热演化的重要分子指纹记录。
      本次研究通过解析含氮杂环化合物结构,建立了响应有机质演化的地球化学新参数。基于含氮杂环化合物的核部与烷基化支链结构组成特征,研究建立了表征核部聚合程度的聚合指数[聚合度P1 = (18 DBE+15 DBE )/12 DBE_N1;DBE (不饱和度) = Double Bond Equivalent]和表征支链烷基化程度的参数[烷基化指数R1= RC6-35/RC0-5;R代表支链,短链=RC0-5、中链=RC6-14和长链=RC15-35]。通过与传统的成熟度指标Ro、TMNr和T/H对比,发现R1与P1是能响应有机质热演化的有效地球化学参数。
      研究还提出了碱性咸化湖相烃源岩“两段式”接力生油机制。基于生物-环境协同演化的地球系统科学思维,将本次工作建立的有机质热演化表征参数与环境参数(古盐度指标β/nCmax等)对比分析,发现高盐(pH)环境抑制含氮杂原子聚合特征明显,尤其是在成熟—高熟阶段,有机质烷基化指数高,指示异常生油潜力。进一步结合咸化湖盆形成过程中成烃生物的差异,发现具有“两段式”接力生油特征:早期蓝细菌生成“成熟油峰”,晚期杜氏藻生成“高熟油”峰(图2)。
      本项工作的核心发现在于提出高盐度(pH)环境通过抑制碱湖相有机质大分子聚合从而延长生油窗,结合成烃生物的演化,形成“双峰接力生油”,丰富了陆相生油新的端元类型,发展了咸化湖盆生烃模式,启示深层高演化勘探需要重视原油,依传统模式评估的天然气潜力可能需要重新审视。准噶尔盆地二叠系碱湖烃源岩是晚古生代大冰期生物-环境协同演化与油气资源效应的典型范例。
      此次研究得到国家自然科学基金重点项目和青年科学基金项目的联合资助。
      论文相关信息:Zhang, J.K., Cao, J., Xiang, B.L., Zhou, N., Ma, W.Y., He, D., 2023. Constraining multi-stage and protracted oil generation of alkaline lacustrine source rocks by heteroatomic compounds. Organic Geochemistry 184, 104668. https://doi.org/10.1016/j.orggeochem.2023.104668.
      图1 碱湖有机质含氮化合物分子结构演化路径重建图
      图2 碱性咸化湖盆烃源岩有机质多阶段生油模式图(碳链断裂为示意性)
    2023-09-11
  • 研究揭示拉伸纪具开口的圆盘状化石为藻类固着器
    科研人员在安徽淮南地区的九里桥组(~950–720 Ma)泥质灰岩中,获得了丰富的以碳质压膜形式保存的、以管状化石与圆盘状化石为主的宏体化石。在“蠕虫状”化石的产出层位发现了大量圆盘状化石,推测是Protoarenicola单独保存的固着器。
      圆盘状和管状化石是元古宙常见的化石类型。由于其形态较为简单,圆盘状化石的亲缘关系和个体发育多处于未知状态。此前的研究显示,一些埃迪卡拉纪具代表性的圆盘状化石,如Hiemalora、Aspidella、Spriggia和Ediacaria,是同层位的底栖埃迪卡拉型宏体化石的离散固着器结构。在成冰纪之前的地层中,同样记录着圆盘状化石与具固着器的管状藻类化石的同层位保存,并且圆盘状化石与固着器之间具有一定的形态相似性,比如它们的中间区域都具有圆心开口等。因此,这种具开口的圆盘状化石也有可能是离散保存的固着器结构,然而这种可能性尚未得到严格的检验。
      我国华北地台胶辽徐淮地区的拉伸纪地层保存了大量的宏体化石,为我们检验上述假说提供了较多的材料。近年来,来自中国科学院南京地质古生物研究所早期生命研究团队的李光金博士、研究员庞科等人,与南京大学、山东科技大学的科研人员合作,在安徽淮南地区的九里桥组(~950–720 Ma)泥质灰岩中,获得了丰富的以碳质压膜形式保存的、以管状化石与圆盘状化石为主的宏体化石。相关成果近日发表在国际地学SCI期刊《古地理、古气候、古生态》(Palaeogeography, Palaeoclimatology, Palaeoecology)上。
      其中,管状化石除常见的Tawuia(塔乌藻)之外,有一类被前人描述为形似“蠕虫”的化石,包括Protoarenicola、Pararenicola以及Sinosabellidites,以发育特征性横纹的管体为主。三类化石的主要区别在于Protoarenicola在管体近端连接着一个圆盘状结构;Pararenicola的管体近端具有一个圆心开口;而Sinosabellidites的管体两端均为封闭状态。在早期的研究中这些“蠕虫状”化石曾被解释为后生动物化石,但在后期研究中人们认为其更有可能是多核体藻类(因此本文将三个属名分别译为:原沙蠋藻Protoarenicola、似沙蠋藻Pararenicola、中华皱节虫藻Sinosabellidites)。“蠕虫状”化石Protoarenicola的圆盘状结构则被解释成固着器,用于将管状藻体吸附于基底,从而营底栖生活。
      科研人员在“蠕虫状”化石的产出层位发现了大量圆盘状化石。部分圆盘状化石被鉴定为元古宙常见的Chuaria(丘尔藻),还有一部分圆盘状化石,因其与Protoarenicola的固着器在形态和大小上均较为相似,研究人员推测是Protoarenicola单独保存的固着器。为检验这一假设,研究人员还开展了详细的形态学、生物统计学和拉曼光谱研究。
      新发现的圆盘状化石以中心位置具有圆形开口为主要特征,开口直径通常小于化石直径的一半;开口边缘保存较多的有机质,而开口内部有机质则相对较少(图1A-F)。研究人员通过对大量标本的测量,结果显示圆盘状化石的直径分布与同层位产出的Chuaria(图1G,H)具有显著差异性,而与Protoarenicola固着器的直径具有相似的分布特征(图2)。更有趣的是,部分同层位产出的Protoarenicola固着器中心也具有开口的特征,且开口边缘可见较多的有机质,内部有机质则相对较少(图3A-M)。测量显示,圆盘状化石中心开口的直径与Protoarenicola固着器的中心开口的直径同样具有相似的分布特征(图2)。
      通过拉曼光谱分析,研究显示圆盘状化石与Chuaria的化学空间(chemospace)无重叠,而与Protoarenicola的固着器具有较大的化学空间重叠(图4)。因此,圆盘状化石被解释为Protoarenicola离散保存的固着器。此外,圆盘状化石的开口直径与不具固着器的Pararenicola藻体近端开口的直径(图3N-P)也具有相似的分布特征(图2),且拉曼化学空间也具有较大重叠区域(图4),暗示圆盘状化石与Pararenicola可能分别为Protoarenicola状藻类的固着器与管状体。
      固着器联结(holdfast coalescence)是在现生底栖藻类中常见的一种现象,即两个或多个藻类个体(或孢子)实现物理接触与融合,随后便共同生长。固着器联结有助于增强藻类锚定基底的能力、加快藻类生长速度和增加藻类繁殖的成功率。淮南地区九里桥组发育多套内碎屑灰岩层和多种沉积构造,如波痕、斜层理以及被截断的叠层石,表明九里桥组沉积环境为中等强度的水动力条件,偶尔受到高强度水动力条件的影响。由于较强的水动力条件会增加藻类被连根拔起的危险,可能促使了圆盘状化石之间(被解释为离散的固着器,图1I-N)以及Protoarenicola固着器之间发生联结作用(图3K-M)。
      研究通过查阅相关文献,发现固着器联结的现象在其他拉伸纪地层产出的底栖藻类中也确实存在,包括金山寨组(~820–720 Ma)和Hulkal组(~900–800 Ma)的Protoarenicola标本、Snail Spring组(~990–775 Ma)的Longfengshania标本;从而研究推测固着器联结可能已经成为拉伸纪底栖藻类为应对较强的水动力环境而普遍采用的策略。
      具开口的圆盘状化石在中元古代-拉伸纪地层Semri群、龙山组(骆驼岭组)、Bhander 群也有发现。如果九里桥组具开口圆盘状化石的解释能够适用于上述标本,那么底栖藻类出现的时间至少可追溯至中元古代早期。底栖藻类在成冰纪之前的海洋生态系统和生物地球化学循环中发挥的作用就很可能被低估了。从中元古代至拉伸纪,具开口的圆盘状化石产地逐渐增多,但其整体形态并未发生大的变化,直到埃迪卡拉纪才出现更多类型的藻类固着器,这种长期的形态停滞可能与成冰纪之前表面具微生物席、缺少生物扰动的基底特征有关。
      本研究得到科技部国家重点研发计划青年科学家项目、国家自然科学基金、中国科学院、现代古生物学和地层学国家重点实验室、中科院青促会、中国博士后科学基金、“深时数字地球”国际大科学计划等联合资助。
      论文相关信息:Li, G., Pang, K.*, Tang, Q., Chen, L., Wu, C., Huang, R., Wan, B., Yuan, X., Zhou, C. 2023. Tonian discoidal fossils from North China: Relating discs to worm-like annulated tubes and their paleoecological and evolutionary implications. Palaeogeography, Palaeoclimatology, Palaeoecology, 628: 111780. https://doi.org/10.1016/j.palaeo.2023.111780.
      图1 具开口的圆盘状化石(A-F, I-N)和Chuaria化石(G, H)
      图2 具开口圆盘状化石、Chuaria和Protoarenicola固着器直径的分布特征(左);圆形开口的直径分布图(右)
      图3 Protoarenicola(A-M)和Pararenicola(N-P)
      图4 拉曼光谱揭示的化学空间分布图
    2023-09-04
  • 自主研发X射线荧光分析仪在贵州龙埋藏学研究中的应用
    南京古生物所改进了目前国际上最先进的大幅面材料表面化学元素扫描设备(如德国Bruke的X射线荧光分析仪M6)存在的缺陷,研制了可以分析不规则、立体化石表面的化学元素分布的X射线荧光无损分析仪,部分创新技术已经在两个发明专利中公开。
      我们在博物馆等场所看到的古生物复原模型通常是根据其骨骼化石与现代生物对比而创作的,充满了人们对力量的渴望以及对健美的想象。然而,由于肌肉和内脏等软体在生物死亡后通常会很快腐烂,无法在地层中保存下来,因此仅通过硬体化石很难复原生物的真实外形。譬如,活跃在2亿多年前的贵州龙,它们的身材是有强健肌肉还是一身肥膘?样貌是像胸前有个大气囊的蜥蜴,抑或是有个大肚子的鳄鱼?
      生物死亡后埋藏在沉积物(如泥沙)中,其肌肉、内脏在腐烂过程中会产生各种化学物质,如大量的有机酸、还原性物质、二氧化碳、硫化氢,甚至氨气等等,这些物质会跟周围的沉积物发生反应形成新的矿物或改变原有的组成,影响范围可能达到几厘米甚至更厚。这些新物质的颜色、结构与围岩基本一样,用肉眼和显微镜通常难以分辨。然而,这些改变了的沉积物却往往有不同于周围沉积物的化学元素背景,因此可以用化石及其围岩表面的化学元素分布,追寻这些新物质也就是生物软体的形状或轮廓的线索。
      常见的表面化学元素分布测量仪器,如电子显微镜及能谱,只能分析毫米级以下尺寸样品。仅有的用来分析大型化石表面化学元素分布的仪器设备,则需要将化石打磨或切割成一个平面并放入真空系统中才能进行准确分析。因为分析条件需要保持固定的样品和X射线光源及检测器之间的距离,样品表面光洁,并排除周围的氧气和氮气。因此这种对样品的破坏性预处理,不能满足我们对珍稀化石标本进行无损研究的需要。
      为解决上述问题,中国科学院南京地质古生物研究所王伟研究员课题组,基于多方面的创新设计,改进了目前国际上最先进的大幅面材料表面化学元素扫描设备(如德国Bruker的X射线荧光分析仪M6)存在的缺陷,研制了可以分析不规则、立体化石表面的化学元素分布的X射线荧光无损分析仪,部分创新技术已经在两个发明专利中公开。
      该自主设计研制的最新设备的技术及原理创新点包括:1)根据化石表面的3D结构形态,确定每个测量点的X射线光源和检测器的空间位置,从而保证每个测量点都有一致的X射线光源到样品及样品到检测器之间的距离,而不需要对化石样品进行磨平破坏;2)用多通道旋转氦气柱在测量区域内形成几乎没有氧气和氮气等的测试环境,有效替代测量所需的真空条件;3)用激光束辅助光线测量化石等样品表面的粗糙度,并对检测到的X射线荧光进行校正,免去了需要对样品表面进行抛光的预处理要求;4)整个系统可简易拆装,方便在不同环境,甚至可以对野外不可移动样品开展无损检测;5)通过多图叠加,可以分析表面积更大的样品。
      课题组利用此设备对一块贵州龙化石表面的钙和铁元素的分布规律进行了初步研究,发现:1)贵州龙前胸部相比较腹部,钙元素分布面积更广,指示其前胸部软体可能更加膨大;2)该贵州龙腐烂降解过程中,其内脏或腐烂产物更有可能从前胸溃烂口以及口腔处形成的通道流出;3)化石标本头部颞窝及附近位置出现元素分布异常,推测该位置可能存在人为修补的可能。
      该设备除了可以用于研究具有不规则表面岩石、化石和文物等表面的化学元素的分布以外,还可以用于分析具有不规则表面的建筑、金属结构材料、野外场地等物质的元素分布。
      作者在文中强调,随着“物联网”和“工业互联网”的广泛应用,满足古生物学家需求的专业设备的设计和开发正在变得简单。技术解决方案和工具设计将成为科学研究的一部分,并将为发现远古生命有关的更新、更有吸引力的证据提供更多的新工具。
      该研究得到中国科学院和国家自然科学基金委员会的联合资助。
      论文相关信息:Wang, W., Shu, L., & Wang, D. (2023). Soft body reconstruction of a reptile fossil by the nondestructive elemental mapping with a newly designed XRF. Island Arc, 32(1), e12495. https://doi.org/10.1111/iar.12495.
      大数据集:Wei WANG, Ling SHU, Deqi WANG. 4887 measured points by XRF under the distance (X-ray source-sample-detector) calibrated [DS/OL]. V1. Science Data Bank, 2022. DOI:10.57760/sciencedb.06605.
      两个相关的已授权发明专利:http://epub.cnipa.gov.cn/patent/CN111624218B;http://epub.cnipa.gov.cn/patent/CN111595883B.
      图1 经过形态校正的化石表面钙元素分布图。
      A为化石标本,B为化石的3D形状模型(红色-黄色等突出部分为凸起的骨骼),C为经形态校正的化石表面的钙元素分布(如躯体和颈部之间的大片区域的钙含量比周围高)
      图2 研制的设备的原理框架图和原型机。
      图3 化石标本上钙和铁的分布。
      (a)和(c)中红色较深部位,可能是软躯体较厚的位置和腐烂产物的排出通道。其中(c)中显示,化石颅部的部分位置(如颞窝)的钙元素分布异常底(浅蓝色),说明岩石存在被人为后期修补的可能
      图4 两种形态(a-c)和表面特征(d-e)的校正机理;克服了国际上最先进的设备需要将珍贵化石标本进行磨平抛光的破坏性分析方法的缺陷。
      图5 设备启动封面界面和软件相应的功能键。
    2023-09-04
  • 藏北羌塘中部中央隆起带中再次发现古特提斯洋重要证据
    为探究古特提斯洋的早期演化及其与原特提斯洋的关系等地质学者长期关注且存在争议的科学问题,中国科学院南京地质古生物研究所科考团队多次前往羌塘盆地中部开展科学考察。在2020年的考察中,科考人员在尼玛县荣玛乡北部冈塘错一带发现了放射虫硅质岩。
      西藏羌塘盆地是青藏高原北部重要的含有多种资源潜力的盆地,近年来也成为油气、矿产资源勘察的重要地区。但羌塘盆地的构造演化一直是学术界关注和争论的焦点。争论的关键科学问题是羌塘盆地中部的中央隆起带(高压变质带)是原位形成的,抑或是由北侧的金沙江带向南俯冲形成的;另一个科学问题则是判断羌塘盆地中部中央隆起带是代表了原特提斯洋至古特提斯洋的连续演化,还是两个洋盆的独立演化。
      为探究古特提斯洋的早期演化及其与原特提斯洋的关系等地质学者长期关注且存在争议的科学问题,中国科学院南京地质古生物研究所科考团队多次前往羌塘盆地中部开展科学考察。在2020年的考察中,科考人员在尼玛县荣玛乡北部冈塘错一带发现了放射虫硅质岩。
      近期,南京古生物所副研究员李鑫、研究员张以春等,日本东北大学准教授铃木纪毅(Noritoshi Suzuki),以及南京大学、中国矿业大学(徐州)等同行合作,针对北部冈塘错一带新发现的放射虫硅质岩展开实验和系统研究,发现了重要的晚泥盆世放射虫动物群。相关研究成果发表于国际地学期刊《冈瓦纳研究》(Gondwana Research)上。
      放射虫是一种海生浮游生物,广布于世界各海洋;其死亡后,骨骼沉落到海洋底面,在水深大于碳酸盐补偿深度(4000–5000 m)的地区沉积,称为放射虫软泥,此后经过成岩作用形成放射虫硅质岩。羌塘盆地中部“中央隆起带变质岩系”中的蛇绿质混杂岩由变质橄榄岩、堆晶岩、辉长岩、玄武岩、硅质岩和灰岩组成。蛇绿质混杂岩中的硅质岩是代表了基性岩之上的沉积盖层,因此硅质岩中的放射虫动物群可以用来限定蛇绿岩的形成时代,进而追溯古大洋的演化历史。
      此次研究在羌塘中部“中央隆起带变质岩系”中发现了晚泥盆世放射虫动物群,其包含Callela parvispinosa Won、Entactinia foveolata Nazarov和 Plenoentactinia pinguis Won等种属。该动物群与前人在双湖县才多茶卡发现的晚泥盆世放射虫构成一个东西向条带,证明羌塘中部的高压变质带具有典型的构造混杂岩特征。研究人员根据晚泥盆世放射虫在特提斯域的分布指出,当时的龙木错双湖缝合带与云南的昌宁–孟连缝合带、泰国的Chiang Mai–Inthanon和Chanthaburi缝合带以及马来西亚的Bentong–Raub缝合带是相连接的,并且共同构成了冈瓦纳和欧亚大陆之间的古特提斯洋主洋盆。
      科研人员综合前人关于发现晚泥盆世古特提斯洋内的放射虫硅质岩沉积在多个地区突然出现,且在缝合带中都缺乏更早的放射虫记录,从而推断古特提斯洋可能在晚泥盆世时期打开。
      该研究得到国家自然科学基金、科技部第二次青藏科考、中国科学院战略先导专项、中国科学院“率先行动”人才项目和深时数字地球国际大科学计划的联合资助。
      论文相关信息:X. Li, N. Suzuki, Y-C Zhang*, H. Zhang, M. Luo, D-X. Yuan, Q-F. Zheng, W-K. Qie, Q. Ju, F. Qiao, H-P. Xu, X-H. Cui, 2024. The central Qiangtang Metamorphic Belt in northern Tibet is an in-situ Paleo-Tethys Ocean: Evidence from newly discovered Late Devonian radiolarians. Gondwana Research, 125, 49–58. https://doi.org/10.1016/j.gr.2023.08.005.
      图1 冈塘错一带黑色硅质岩中晚泥盆世放射虫动物群
      图2 欧亚地区晚泥盆世放射虫动物群分布
      图3 古特提斯洋的演化及龙木错–双湖缝合带的形成
    2023-08-22
  • 华南晚奥陶世生物礁揭示冰室气候下的混合型碳酸盐岩记录
    近期,中国科学院南京地质古生物研究所副研究员李启剑、研究员李越等科研人员,与英国布鲁内尔大学教授Stephen Kershaw及曲阜师范大学等的相关学者对浙赣交界的晚奥陶世生物礁开展了多次联合野外考察,揭示了华南晚奥陶世冰室气候下的混合型碳酸盐岩记录。
      纵观46亿年的地质历史,全球可识别出“温室气候”与“冰室气候”两种大的气候类型;两类气候相互交替出现,持续时间长短不一。其中,冰室气候类型又可进一步划分为寒冷“冰期”与冰期之间较为温暖的“间冰期”。
      在距今4.85-4.43亿年前的奥陶纪,世界各地的岩石中不仅记录了海洋生态系统中的一次大型生物辐射事件,而且还为生物演化的关键时期从“温室气候”向“冰室气候”的转变提供了诸多证据。
      近期,中国科学院南京地质古生物研究所副研究员李启剑、研究员李越等科研人员,与英国布鲁内尔大学教授Stephen Kershaw及曲阜师范大学等的相关学者对浙赣交界的晚奥陶世生物礁开展了多次联合野外考察,揭示了华南晚奥陶世冰室气候下的混合型碳酸盐岩记录。相关成果于近期在国际期刊《三古》(Palaeogeography,Palaeoclimatology,Palaeoecology)上发表。
      研究人员在实验室运用大规模磨制抛光面并有针对性地配合显微薄片,结合阴极发光等研究手段,揭示了江西玉山鸡头山剖面三衢山组下段礁灰岩中“串管海绵-钙质微生物-同沉积胶结物”三位一体的独特构造。该构造常表现为“葡萄串”状的串管海绵与珊瑚形钙质疑问生物Amsassia相互缠绕,形成生物礁格架岩的基本支撑结构,并被钙质微生物和大量胶结物包裹加固。薄片中阴极发光结果表明胶结物至少包括3个世代,最早的一个世代为等厚胶结物,以暗淡的阴极发光为特征,显著区别于后两个世代,代表了同沉积期的产物。
      研究结果表明:浅海同沉积胶结作用在中-晚奥陶世的生物礁中显著增强。丰富的同沉积胶结物在现代珊瑚礁的构建起到至关重要的作用,为骨骼堆积形成的礁格架提供了不同程度抗浪能力和刚性结构。然而,在奥陶系生物礁的相关研究中,同沉积胶结物的作用被长期忽视,直到近年来在北美和我国华北才有个别案例被报道,此类胶结物在礁体中的作用才得到关注。
      结合以上案例,华南江西三衢山组的生物礁代表了冰室气候下典型的混合组份型碳酸盐岩记录:后生动物骨骼、钙质微生物和同沉积胶结物共同构建了此类礁体。除了古气候等环境因素,伴随着生物辐射事件的发生,不断增强的海底生物扰动等生物反馈因素也可能对同沉积胶结物的广泛发育起到重要作用。
      本研究得到了国家自然科学基金委、中国科学院青年创新促进会等的资助。
      论文相关信息: Li, Q.J.*, Na, L., Yu, S.Y., Mao, Y.Y., Kershaw, S., Yue, L., 2023. Katian (Late Ordovician) sphinctozoan-bearing reefs: Hybrid carbonates before the glacial maximum. Palaeogeography, Palaeoclimatology, Palaeoecology. 624(15): 111642. https://doi.org/10.1016/j.palaeo.2023.111642.
      图1. 玉山鸡头山剖面三衢山组下段生物礁微相照片。A. 生物礁格架岩,显示丛花海绵(Co)等生物骨骼原地堆积形成的支撑结构;B. 丛花海绵与珊瑚形钙质疑问生物Amsassia(Am)的钙质骨骼相互缠绕形成的生物礁格架细节C. 丛花海绵化石(Co)及其外管(Ex)结构细节(黄色三角显示海绵化石外壁,红色三角显示沿内壁生长的同沉积胶结物);D.钙质微生物(Al)结壳包裹在 丛花海绵(Co)外壁表面。
      图2. 生物礁中胶结物的细节。A&C: 单偏光显微照片;B&D: 阴极发光显微照片(数字标注不同世代的胶结物,黄色三角标注同一视域不同照片之间的定位点)。
      图3. 奥陶纪生物礁中生物组成及非生物组份的变迁,显示海底同沉积胶结作用的显著加强。
    2023-08-16
  • 硅酸盐硼同位素测定方法获得发明专利授权
    近期,中国科学院南京地质古生物研究所与东华理工大学合作研发的一种基于水解Na2O2碱融法的硅酸盐硼同位素测定方法获得发明专利授权(授权公告号:CN 116067740B)。
      近期,中国科学院南京地质古生物研究所与东华理工大学合作研发的一种基于水解Na2O2碱融法的硅酸盐硼同位素测定方法获得发明专利授权(授权公告号:CN 116067740B)。
      硼同位素是地球与行星科学研究中的一个重要工具。但是精确测量硅酸盐的硼同位素存在一定的挑战,其主要原因源于样品消解。碱熔法是一种适合于硅酸盐样品的熔样方法。可目前用于测量硅酸盐硼同位素的碱熔法采用的铂金价格昂贵,成本高;或是玻璃碳坩埚和较高的助熔剂比例导致测量效率低等问题。而且,现有的碱融法在样品和试剂前处理过程中存在工艺流程复杂和准确性较差的问题。
      为了解决现有技术中的难题,本发明提供了一种安全且高效的硅酸盐硼同位素测定方法。该方法以水合过氧化钠作为助溶剂,采用廉价的银坩埚和马弗炉,在最大限度降低助溶剂用量的同时实现了硅酸盐样品硼含量和硼同位素组成的精准测试。该方法对地球深部水循环、矿产资源勘探、地球与行星演化等研究领域具有重大的作用。
      
    2023-08-14
  • Science发表原论文作者团队对两篇评述云南虫论文的回应
    原论文报道了云南虫化石的鳃弓由叠盘状软骨细胞结构和含有微原纤维构造的细胞外基质组成,被认为符合脊椎动物的特征。研究还通过系统发育分析,显示云南虫最有可能是基干脊椎动物。
      2022年7月8日,中国科学院南京地质古生物研究所研究员朱茂炎领衔的“地球-生命系统早期演化”研究团队和南京大学地球科学与工程学院教授姜宝玉课题组合作在《科学》(Science)期刊上发表了澄江动物群云南虫化石的研究论文<!--[if supportFields]>ADDIN
      CSL_CITATION {"citationItems":[{"id":"ITEM-1","itemData":{"DOI":"10.1126/science.abm2708","ISSN":"0036-8075","abstract":"Pharyngeal
      arches are a key innovation that likely contributed to the evolution of the
      jaws and braincase of vertebrates. It has long been hypothesized that the
      pharyngeal (branchial) arch evolved from an unjointed cartilaginous rod in
      vertebrate ancestors such as that in the nonvertebrate chordate amphioxus, but
      whether such ancestral anatomy existed remains unknown. The pharyngeal skeleton
      of controversial Cambrian animals called yunnanozoans may contain the oldest
      fossil evidence constraining the early evolution of the arches, yet its
      correlation with that of vertebrates is still disputed. By examining additional
      specimens in previously unexplored techniques (for example, x-ray
      microtomography, scanning and transmission electron microscopy, and energy
      dispersive spectrometry element mapping), we found evidence that yunnanozoan
      branchial arches consist of cellular cartilage with an extracellular matrix
      dominated by microfibrils, a feature hitherto considered specific to
      vertebrates. Our phylogenetic analysis provides further support that
      yunnanozoans are stem
      vertebrates.","author":[{"dropping-particle":"","family":"Tian","given":"Qingyi","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Zhao","given":"Fangchen","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Zeng","given":"Han","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Zhu","given":"Maoyan","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Jiang","given":"Baoyu","non-dropping-particle":"","parse-names":false,"suffix":""}],"container-title":"Science","id":"ITEM-1","issue":"6602","issued":{"date-parts":[["2022","7","8"]]},"language":"English","page":"218-222","publisher-place":"Nanjing
      Univ, Sch Earth Sci & Engn, State Key Lab Mineral Deposits Res, Nanjing
      210023, Peoples R China","title":"Ultrastructure reveals
      ancestral vertebrate pharyngeal skeleton in
      yunnanozoans","type":"article-journal","volume":"377"},"uris":["http://www.mendeley.com/documents/?uuid=8e7aa11e-5639-49f8-914a-a5390d8556aa"]}],"mendeley":{"formattedCitation":"(Tian
      et al., 2022)","plainTextFormattedCitation":"(Tian et al.,
      2022)","previouslyFormattedCitation":"(Tian et al.,
      2022)"},"properties":{"noteIndex":0},"schema":"https://github.com/citation-style-language/schema/raw/master/csl-citation.json"}<![endif]-->(Tian et al., 2022)<!--[if supportFields]><![endif]-->(以下称为原论文)。原论文报道了云南虫化石的鳃弓由叠盘状软骨细胞结构和含有微原纤维构造的细胞外基质组成,被认为符合脊椎动物的特征。研究还通过系统发育分析,显示云南虫最有可能是基干脊椎动物。
      2023年7月28日,《科学》(Science)同时发表了两篇针对原论文的评述文章和原论文作者团队的回应文章。在第一篇评述中,He等对云南虫叠盘状软骨细胞结构和微原纤维基质的解释提出了不同观点,并据此定义了不同于原论文的云南虫分类位置<!--[if supportFields]>ADDIN
      CSL_CITATION
      {"citationItems":[{"id":"ITEM-1","itemData":{"DOI":"10.1126/science.ade9707","ISSN":"0036-8075","abstract":"Tian
      et al . (Research Articles, 8 July 2022, abm2708) hypothesized that
      yunnanozoans are stem-group vertebrates on the basis of “cellular cartilage”,
      “fibrillin microfibers”, and “subchordal rod” associated with the branchial
      arches of yunnanozoans. However, we reject the presence of cellular cartilage,
      fibrillin, and the phylogenetic proposal of vertebrate affinities based on
      ultrastructure and morphology of yunnanozoans from more than 8000
      specimens.","author":[{"dropping-particle":"","family":"He","given":"Kaiyue","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Liu","given":"Jianni","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Han","given":"Jian","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Ou","given":"Qiang","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Chen","given":"Ailin","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Zhang","given":"Zhifei","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Fu","given":"Dongjing","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Hua","given":"Hong","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Zhang","given":"Xingliang","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Shu","given":"Degan","non-dropping-particle":"","parse-names":false,"suffix":""}],"container-title":"Science","id":"ITEM-1","issue":"6656","issued":{"date-parts":[["2023","7","28"]]},"title":"Comment
      on “Ultrastructure reveals ancestral vertebrate pharyngeal skeleton in
      yunnanozoans”","type":"article-journal","volume":"381"},"uris":["http://www.mendeley.com/documents/?uuid=f0dbeaa9-a57a-4355-ba26-87afee92ff91"]}],"mendeley":{"formattedCitation":"(He
      et al., 2023)","plainTextFormattedCitation":"(He et al.,
      2023)","previouslyFormattedCitation":"(He et al., 2023)"},"properties":{"noteIndex":0},"schema":"https://github.com/citation-style-language/schema/raw/master/csl-citation.json"}<![endif]-->(He et al., 2023)<!--[if supportFields]><![endif]-->。在第二篇评述中,Zhang和Pratt认为纳米尺度的微原纤维不可能从寒武纪保存至今,微原纤维构造可能是现代污染物<!--[if supportFields]>ADDIN
      CSL_CITATION {"citationItems":[{"id":"ITEM-1","itemData":{"DOI":"10.1126/science.adf1472","ISSN":"0036-8075","abstract":"Tian
      et al . (Reports, 8 July 2022, p. 218) claim that Cambrian yunnanozoan animals
      are stem vertebrates, based partly on their observation at the nanometer scale
      of microfibrillar tissue located in the branchial arches. They interpret this
      to represent cellular cartilage with an extracellular matrix of microfibrils.
      Instead, we argue that the ‘microfibrils’ are more likely modern organic
      contamination.","author":[{"dropping-particle":"","family":"Zhang","given":"Xi-guang","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Pratt","given":"Brian
      R.","non-dropping-particle":"","parse-names":false,"suffix":""}],"container-title":"Science","id":"ITEM-1","issue":"6656","issued":{"date-parts":[["2023","7","28"]]},"title":"Comment
      on “Ultrastructure reveals ancestral vertebrate pharyngeal skeleton in
      yunnanozoans”","type":"article-journal","volume":"381"},"uris":["http://www.mendeley.com/documents/?uuid=4f3b128b-47fd-4770-ad35-0c38f4be2ecf"]}],"mendeley":{"formattedCitation":"(Zhang
      and Pratt, 2023)","plainTextFormattedCitation":"(Zhang and
      Pratt, 2023)","previouslyFormattedCitation":"(Zhang and
      Pratt, 2023)"},"properties":{"noteIndex":0},"schema":"https://github.com/citation-style-language/schema/raw/master/csl-citation.json"}<![endif]-->(Zhang and Pratt, 2023)<!--[if supportFields]><![endif]-->。对于两篇评述文章,原论文团队的回应文章展示了新的形态学和化学证据,进一步支持了原论文的解释<!--[if supportFields]>ADDIN
      CSL_CITATION {"citationItems":[{"id":"ITEM-1","itemData":{"DOI":"10.1126/science.adf3363","ISSN":"0036-8075","abstract":"He
      et al . dispute our anatomical interpretations on the structures of cellular
      chambers and microfibrils in yunnanozoan branchial arches and put forward
      alternative interpretations on these structures. Zhang and Pratt argue that the
      microfibrils we identified in yunnanozoans are more likely modern organic
      contamination. Here we provide additional evidence to support our
      interpretations and dismiss the alternative
      interpretations.","author":[{"dropping-particle":"","family":"Tian","given":"Qingyi","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Zhao","given":"Fangchen","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Zeng","given":"Han","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Zhu","given":"Maoyan","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Jiang","given":"Baoyu","non-dropping-particle":"","parse-names":false,"suffix":""}],"container-title":"Science","id":"ITEM-1","issue":"6656","issued":{"date-parts":[["2023","7","28"]]},"title":"Response
      to Comments on “Ultrastructure reveals ancestral vertebrate pharyngeal skeleton
      in
      yunnanozoans”","type":"article-journal","volume":"381"},"uris":["http://www.mendeley.com/documents/?uuid=a6124633-3369-4437-807d-7fc325520984"]}],"mendeley":{"formattedCitation":"(Tian
      et al., 2023)","plainTextFormattedCitation":"(Tian et al.,
      2023)","previouslyFormattedCitation":"(Tian et al.,
      2023)"},"properties":{"noteIndex":0},"schema":"https://github.com/citation-style-language/schema/raw/master/csl-citation.json"}<![endif]-->(Tian et al., 2023)<!--[if supportFields]><![endif]-->。
      He等认为鳃棒是中空的管状结构,鳃棒的细胞状结构是中空的鳃丝根部形态(图1A)。但是,He等评述文章中展示的化石照片(图1B)显示鳃棒并非中空,含有紧密堆叠的细胞状结构。这些细胞状结构与鳃丝并没有一一对应(图1C)。原作者团队的显微CT扫描数据从多个角度揭示鳃棒不是中空的,而是由多排2–3个细胞状结构组成。这些细胞状结构呈密闭的空心球状,与鳃棒两侧的鳃丝并不相通,排除了是鳃丝根部形态的可能(图2)。
      图1.云南虫鳃弓形态。(A)He等评述文章中的鳃弓复原图认为鳃棒呈中空管状。(B–C)原作者团队根据He等提供的化石照片(B)重新解释了鳃棒内部并非中空,而是由多排2–3个细胞状结构组成(C)。(A–B)来自<!--[if supportFields]>ADDIN CSL_CITATION
      {"citationItems":[{"id":"ITEM-1","itemData":{"DOI":"10.1126/science.ade9707","ISSN":"0036-8075","abstract":"Tian
      et al . (Research Articles, 8 July 2022, abm2708) hypothesized that yunnanozoans
      are stem-group vertebrates on the basis of “cellular cartilage”, “fibrillin
      microfibers”, and “subchordal rod” associated with the branchial arches of
      yunnanozoans. However, we reject the presence of cellular cartilage, fibrillin,
      and the phylogenetic proposal of vertebrate affinities based on ultrastructure
      and morphology of yunnanozoans from more than 8000
      specimens.","author":[{"dropping-particle":"","family":"He","given":"Kaiyue","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Liu","given":"Jianni","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Han","given":"Jian","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Ou","given":"Qiang","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Chen","given":"Ailin","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Zhang","given":"Zhifei","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Fu","given":"Dongjing","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Hua","given":"Hong","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Zhang","given":"Xingliang","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Shu","given":"Degan","non-dropping-particle":"","parse-names":false,"suffix":""}],"container-title":"Science","id":"ITEM-1","issue":"6656","issued":{"date-parts":[["2023","7","28"]]},"title":"Comment
      on “Ultrastructure reveals ancestral vertebrate pharyngeal skeleton in
      yunnanozoans”","type":"article-journal","volume":"381"},"uris":["http://www.mendeley.com/documents/?uuid=f0dbeaa9-a57a-4355-ba26-87afee92ff91"]}],"mendeley":{"formattedCitation":"(He
      et al., 2023)","manualFormatting":"(He et al.,
      2023)","plainTextFormattedCitation":"(He
      et al., 2023)","previouslyFormattedCitation":"(He et al.,
      2023)"},"properties":{"noteIndex":0},"schema":"https://github.com/citation-style-language/schema/raw/master/csl-citation.json"}<![endif]-->(He et al., 2023)<!--[if supportFields]><![endif]-->,(C)来自<!--[if supportFields]>ADDIN CSL_CITATION {"citationItems":[{"id":"ITEM-1","itemData":{"DOI":"10.1126/science.adf3363","ISSN":"0036-8075","abstract":"He
      et al . dispute our anatomical interpretations on the structures of cellular
      chambers and microfibrils in yunnanozoan branchial arches and put forward
      alternative interpretations on these structures. Zhang and Pratt argue that the
      microfibrils we identified in yunnanozoans are more likely modern organic
      contamination. Here we provide additional evidence to support our
      interpretations and dismiss the alternative
      interpretations.","author":[{"dropping-particle":"","family":"Tian","given":"Qingyi","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Zhao","given":"Fangchen","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Zeng","given":"Han","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Zhu","given":"Maoyan","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Jiang","given":"Baoyu","non-dropping-particle":"","parse-names":false,"suffix":""}],"container-title":"Science","id":"ITEM-1","issue":"6656","issued":{"date-parts":[["2023","7","28"]]},"title":"Response
      to Comments on “Ultrastructure reveals ancestral vertebrate pharyngeal skeleton
      in
      yunnanozoans”","type":"article-journal","volume":"381"},"uris":["http://www.mendeley.com/documents/?uuid=a6124633-3369-4437-807d-7fc325520984"]}],"mendeley":{"formattedCitation":"(Tian
      et al., 2023)","plainTextFormattedCitation":"(Tian et al.,
      2023)","previouslyFormattedCitation":"(Tian et al.,
      2023)"},"properties":{"noteIndex":0},"schema":"https://github.com/citation-style-language/schema/raw/master/csl-citation.json"}<![endif]-->(Tian et al., 2023)<!--[if supportFields]><![endif]-->。
      图2.回应文章中展示的云南虫鳃弓的CT三维渲染和切片。(A)鳃棒内部并不是中空管状,而是由多排细胞状结构组成。(B–F)三个方向的切片都显示细胞状结构是密闭空心的,与鳃丝并不相通,不是鳃丝根部底座。比例尺均为100 μm。修改自<!--[if supportFields]>ADDIN CSL_CITATION
      {"citationItems":[{"id":"ITEM-1","itemData":{"DOI":"10.1126/science.adf3363","ISSN":"0036-8075","abstract":"He
      et al . dispute our anatomical interpretations on the structures of cellular
      chambers and microfibrils in yunnanozoan branchial arches and put forward
      alternative interpretations on these structures. Zhang and Pratt argue that the
      microfibrils we identified in yunnanozoans are more likely modern organic
      contamination. Here we provide additional evidence to support our
      interpretations and dismiss the alternative
      interpretations.","author":[{"dropping-particle":"","family":"Tian","given":"Qingyi","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Zhao","given":"Fangchen","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Zeng","given":"Han","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Zhu","given":"Maoyan","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Jiang","given":"Baoyu","non-dropping-particle":"","parse-names":false,"suffix":""}],"container-title":"Science","id":"ITEM-1","issue":"6656","issued":{"date-parts":[["2023","7","28"]]},"title":"Response
      to Comments on “Ultrastructure reveals ancestral vertebrate pharyngeal skeleton
      in
      yunnanozoans”","type":"article-journal","volume":"381"},"uris":["http://www.mendeley.com/documents/?uuid=a6124633-3369-4437-807d-7fc325520984"]}],"mendeley":{"formattedCitation":"(Tian
      et al., 2023)","plainTextFormattedCitation":"(Tian et al.,
      2023)","previouslyFormattedCitation":"(Tian et al.,
      2023)"},"properties":{"noteIndex":0},"schema":"https://github.com/citation-style-language/schema/raw/master/csl-citation.json"}<![endif]-->(Tian et al., 2023)<!--[if supportFields]><![endif]-->。
      He等评述还认为微原纤维可能是黏土矿物。但是,黏土矿物主要由硅、铝、镁、铁元素组成。回应中新的元素分析结果再次显示微原纤维以碳元素为主(图3),与原论文中的元素和光谱分析结果一致<!--[if supportFields]>ADDIN CSL_CITATION {"citationItems":[{"id":"ITEM-1","itemData":{"DOI":"10.1126/science.abm2708","ISSN":"0036-8075","abstract":"Pharyngeal
      arches are a key innovation that likely contributed to the evolution of the
      jaws and braincase of vertebrates. It has long been hypothesized that the
      pharyngeal (branchial) arch evolved from an unjointed cartilaginous rod in
      vertebrate ancestors such as that in the nonvertebrate chordate amphioxus, but
      whether such ancestral anatomy existed remains unknown. The pharyngeal skeleton
      of controversial Cambrian animals called yunnanozoans may contain the oldest
      fossil evidence constraining the early evolution of the arches, yet its
      correlation with that of vertebrates is still disputed. By examining additional
      specimens in previously unexplored techniques (for example, x-ray
      microtomography, scanning and transmission electron microscopy, and energy
      dispersive spectrometry element mapping), we found evidence that yunnanozoan
      branchial arches consist of cellular cartilage with an extracellular matrix
      dominated by microfibrils, a feature hitherto considered specific to
      vertebrates. Our phylogenetic analysis provides further support that
      yunnanozoans are stem
      vertebrates.","author":[{"dropping-particle":"","family":"Tian","given":"Qingyi","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Zhao","given":"Fangchen","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Zeng","given":"Han","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Zhu","given":"Maoyan","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Jiang","given":"Baoyu","non-dropping-particle":"","parse-names":false,"suffix":""}],"container-title":"Science","id":"ITEM-1","issue":"6602","issued":{"date-parts":[["2022","7","8"]]},"language":"English","page":"218-222","publisher-place":"Nanjing
      Univ, Sch Earth Sci & Engn, State Key Lab Mineral Deposits Res, Nanjing
      210023, Peoples R China","title":"Ultrastructure reveals
      ancestral vertebrate pharyngeal skeleton in
      yunnanozoans","type":"article-journal","volume":"377"},"uris":["http://www.mendeley.com/documents/?uuid=8e7aa11e-5639-49f8-914a-a5390d8556aa"]}],"mendeley":{"formattedCitation":"(Tian
      et al., 2022)","plainTextFormattedCitation":"(Tian et al.,
      2022)","previouslyFormattedCitation":"(Tian et al.,
      2022)"},"properties":{"noteIndex":0},"schema":"https://github.com/citation-style-language/schema/raw/master/csl-citation.json"}<![endif]-->(Tian et al., 2022)<!--[if supportFields]><![endif]-->。这说明微原纤维不是黏土矿物,而是有机残留物。
      图3. 透射电镜样品的高角环形暗场像(HAADF-STEM)和能量色散X射线光谱,显示了化石微原纤维区域主要由碳元素组成。修改自<!--[if supportFields]>ADDIN CSL_CITATION
      {"citationItems":[{"id":"ITEM-1","itemData":{"DOI":"10.1126/science.adf3363","ISSN":"0036-8075","abstract":"He
      et al . dispute our anatomical interpretations on the structures of cellular
      chambers and microfibrils in yunnanozoan branchial arches and put forward
      alternative interpretations on these structures. Zhang and Pratt argue that the
      microfibrils we identified in yunnanozoans are more likely modern organic
      contamination. Here we provide additional evidence to support our
      interpretations and dismiss the alternative
      interpretations.","author":[{"dropping-particle":"","family":"Tian","given":"Qingyi","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Zhao","given":"Fangchen","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Zeng","given":"Han","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Zhu","given":"Maoyan","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Jiang","given":"Baoyu","non-dropping-particle":"","parse-names":false,"suffix":""}],"container-title":"Science","id":"ITEM-1","issue":"6656","issued":{"date-parts":[["2023","7","28"]]},"title":"Response
      to Comments on “Ultrastructure reveals ancestral vertebrate pharyngeal skeleton
      in
      yunnanozoans”","type":"article-journal","volume":"381"},"uris":["http://www.mendeley.com/documents/?uuid=a6124633-3369-4437-807d-7fc325520984"]}],"mendeley":{"formattedCitation":"(Tian
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      Zhang和Pratt认为含有微原纤维的碳膜可能是覆盖在化石表面的现代有机污染物。回应文章中逐步放大的扫描电镜照片显示,不同于现代污染物是覆盖在化石和沉积物表面的,含有微原纤维的碳膜嵌入了沉积物之中(图4)。同时,回应文章指出原论文中碳膜的傅里叶红外光谱(FTIR)和地质历史时期形成的有机残留物相似,都具有明显的脂肪族CH3、CH2和芳香族C=C吸收峰,且缺失现代有机物的一系列特征吸收峰,排除了来源于现代污染物的可能。
      图4.逐步放大的扫描电镜照片。(A–F)在化石表面,碳膜上有沉积物颗粒覆盖;(G–L)在化石截面上,碳膜被紧紧地夹在两层沉积物之间。红色三角形指示沉积物颗粒,白色三角形指示微原纤维构造。来自<!--[if supportFields]>ADDIN CSL_CITATION {"citationItems":[{"id":"ITEM-1","itemData":{"DOI":"10.1126/science.adf3363","ISSN":"0036-8075","abstract":"He
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      alternative interpretations on these structures. Zhang and Pratt argue that the
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      interpretations and dismiss the alternative
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      上述新证据进一步支持了云南虫具有脊椎动物特有的软骨鳃弓,且含有微原纤维的碳膜是古代有机物,排除了评述中推测的黏土矿物或现代有机污染物的可能。原论文发表的一年以来,受到了全世界学者的广泛关注。截止至2023年7月28日,Web of Science数据库显示原论文已被他人引用6次。其中,5篇论文接受了原论文提出的云南虫属于脊椎动物干群的观点<!--[if supportFields]>ADDIN CSL_CITATION {"citationItems":[{"id":"ITEM-1","itemData":{"DOI":"10.1111/1755-6724.15027","ISSN":"1000-9515","abstract":"Systematic
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      of view, as major evolutionary transitions. In order to fill these
      morphological gaps and to map the evolutionary steps toward major evolutionary
      transitions, we need to integrate extinct stem-group taxa in phylogenetic
      studies. However, the recognition of stem group has not been widely adopted in
      the study of early animal fossils, despite that all fossils are stem groups at
      one level or another. Part of the difficulty is that stem groups may not have
      all features that collectively diagnose the respective crown group, and they
      can have unique (autapomorphic) features, making them tantalizingly similar to
      and frustratingly different from the crown group (e.g., stem-group eukaryotes
      can be prokaryotic and stem-group animals can be protistan). The need to
      embrace stem groups and to implement the PhyloCode, in order to achieve
      phylogenetic clarity and to offer key paleontological insights into the origin
      and early animal evolution, is illustrated in debates on several controversial
      Ediacaran and Cambrian
      fossils.","author":[{"dropping-particle":"","family":"Xiao","given":"Shuhai","non-dropping-particle":"","parse-names":false,"suffix":""}],"container-title":"Acta
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      anatomy of the Tully monster casts doubt on its presumed vertebrate
      affinities","type":"article-journal","volume":"66"},"uris":["http://www.mendeley.com/documents/?uuid=0978eb2a-f18c-4c19-9531-8a1a8c278772"]},{"id":"ITEM-3","itemData":{"DOI":"10.1111/ede.12433","ISSN":"1520-541X","author":[{"dropping-particle":"","family":"Onai","given":"Takayuki","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Aramaki","given":"Toshihiro","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Takai","given":"Akira","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Kakiguchi","given":"Kisa","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Yonemura","given":"Shigenobu","non-dropping-particle":"","parse-names":false,"suffix":""}],"container-title":"Evolution
      &
      Development","id":"ITEM-3","issue":"November
      2022","issued":{"date-parts":[["2023","3","22"]]},"page":"1-12","title":"Cranial
      cartilages: Players in the evolution of the cranium during evolution of the
      chordates in general and of the vertebrates in
      particular","type":"article-journal"},"uris":["http://www.mendeley.com/documents/?uuid=6d3d3fe6-cb8d-4e43-8fbe-55ce9d4877ef"]},{"id":"ITEM-4","itemData":{"DOI":"10.1093/zoolinnean/zlac086","ISSN":"0024-4082","abstract":"This
      paper addresses a recent claim by Miyashita and co-authors that the
      filter-feeding larval lamprey is a new evolutionary addition to the lamprey life-cycle
      and does not provide information about early vertebrates, in contrast to the
      traditional view that this ammocoete stage resembles the first vertebrates. The
      evidence behind this revolutionary claim comes from fossil lampreys from
      360–306 Mya that include young stages – even yolk-sac hatchlings – with adult
      (predacious) feeding structures. However, the traditional view is not so easily
      dismissed. The phylogeny on which the non-ammocoete theory is based was not
      tested in a statistically meaningful way. Additionally, the target article did
      not consider the known evidence for the traditional view, namely that the
      complex filter-feeding structures are highly similar in ammocoetes and the
      invertebrate chordates, amphioxus and tunicates. In further support of the
      traditional view, I show that ammocoetes are helpful for reconstructing the
      first vertebrates and the jawless, fossil stem gnathostomes called ostracoderms
      – their pharynx, oral cavity, mouth opening, lips and filter-feeding mode (but,
      ironically, not their mandibular/jaw region). From these considerations, I
      offer a scenario for the evolution of vertebrate life-cycles that fits the
      traditional, ammocoete-informed theory and puts filter feeding at centre
      stage.","author":[{"dropping-particle":"","family":"Mallatt","given":"Jon","non-dropping-particle":"","parse-names":false,"suffix":""}],"container-title":"Zoological
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      origins are informed by larval lampreys (ammocoetes): a response to Miyashita
      et al. ,
      2021","type":"article-journal","volume":"197"},"uris":["http://www.mendeley.com/documents/?uuid=4b0c9e49-015d-4d9b-b3f3-58d1e7afbe79"]},{"id":"ITEM-5","itemData":{"DOI":"10.1111/ede.12422","ISSN":"1520-541X","author":[{"dropping-particle":"","family":"Johanson","given":"Zerina","non-dropping-particle":"","parse-names":false,"suffix":""}],"container-title":"Evolution
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      Development","id":"ITEM-5","issue":"1","issued":{"date-parts":[["2023","1","29"]]},"page":"119-133","title":"Vertebrate
      cranial evolution: Contributions and conflict from the fossil
      record","type":"article-journal","volume":"25"},"uris":["http://www.mendeley.com/documents/?uuid=ae9ae377-ffcc-4ef2-97e9-89ca35e89c2c"]}],"mendeley":{"formattedCitation":"(Johanson,
      2023; Mallatt, 2023; Mikami et al., 2023; Onai et al., 2023; Xiao,
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      Mallatt, 2023; Mikami et al., 2023; Onai et al., 2023; Xiao,
      2022)","previouslyFormattedCitation":"(Johanson, 2023;
      Mallatt, 2023; Mikami et al., 2023; Miyashita, 2022; Onai et al., 2023; Xiao,
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      {"citationItems":[{"id":"ITEM-1","itemData":{"DOI":"10.3389/feart.2023.1120118","ISSN":"2296-6463","abstract":"Genic
      and genomic data have been reshaping our understanding of the earliest
      radiation event of metazoans, the well-known Cambrian Evolutionary Radiation,
      not only from the respects of reshuffling the phylogenetic topologies of some
      animal phyla but by deciphering the deep homologies of many morphological
      features. These advances, together with the continuing discoveries of the
      Ediacaran-Cambrian fossils, are unveiling the cladogenetic process of the early
      metazoans and the patterns of morphologic evolution during this biological
      radiation event. In this review, I focus on a small but challenging field, the
      problematic fossils from the early Cambrian fossil Lagerst?tten, such as the
      Chengjiang biota, mainly on the controversies concerning their interpretation
      and the consequent impacts on understanding the early evolution of animals. The
      bizarre body plans of the early Cambrian problematica alone do not account for
      the difficulties in studying their biology and affinity. Instead, it is the
      combined action of the taphonomic artifacts and the uncertainty in homologizing
      the preserved characters that impede generating plausible interpretations.
      Despite all these issues, a testable and repeatable method for interpreting
      fossils has emerged and is becoming more practicable. The integration of an
      evolutionary-grade conceptual frame is beneficial to the interpretation of the
      Cambrian problematic fossils. Together with the focus on taphonomic alternation
      and homologic assessment, the Cambrian problematic fossils are becoming more
      informative nodes in the “parsing tree” of early animal
      evolution.","author":[{"dropping-particle":"","family":"Cong","given":"Peiyun","non-dropping-particle":"","parse-names":false,"suffix":""}],"container-title":"Frontiers
      in Earth
      Science","id":"ITEM-1","issue":"May","issued":{"date-parts":[["2023","5","10"]]},"page":"1-13","title":"The
      early animal radiation: insights from interpreting the Cambrian problematic
      fossils","type":"article-journal","volume":"11"},"uris":["http://www.mendeley.com/documents/?uuid=16e1f35c-821f-4f2a-bbc9-091fc6315628"]}],"mendeley":{"formattedCitation":"(Cong,
      2023)","plainTextFormattedCitation":"(Cong,
      2023)","previouslyFormattedCitation":"(Cong,
      2023)"},"properties":{"noteIndex":0},"schema":"https://github.com/citation-style-language/schema/raw/master/csl-citation.json"}<![endif]-->(Cong, 2023)<!--[if supportFields]><![endif]-->。
      该回应文章的发表得到了中国科学院战略性先导科技专项(B类)、国家自然科学基金委、现代古生物学和地层学国家重点实验室、南京大学优秀博士研究生创新能力提升计划等基金的大力支持。
      原论文相关信息:
      Tian, Q., Zhao, F., Zeng, H., Zhu, M., Jiang, B., 2022. Ultrastructure reveals ancestral vertebrate pharyngeal skeleton in yunnanozoans. Science. 377, 218–222. https://doi.org/10.1126/science.abm2708.
       
      回应文章相关信息:
      Tian, Q., Zhao, F., Zeng, H., Zhu, M., Jiang, B., 2023. Response to Comments on “Ultrastructure reveals ancestral vertebrate pharyngeal skeleton in yunnanozoans.” Science. 381, eadf3363. https://doi.org/10.1126/science.adf3363.
       
      评述文章相关信息:
      He, K., Liu, J., Han, J., Ou, Q., Chen, A., Zhang, Z., Fu, D., Hua, H., Zhang, X., Shu, D., 2023. Comment on “Ultrastructure reveals ancestral vertebrate pharyngeal skeleton in yunnanozoans.” Science. 381, eade9707. https://doi.org/10.1126/science.ade9707.
      Zhang, X., Pratt, B.R., 2023. Comment on “Ultrastructure reveals ancestral vertebrate pharyngeal skeleton in yunnanozoans.” Science. 381, eadf1472. https://doi.org/10.1126/science.adf1472.
       
      参考文献:
      Cong, P., 2023. The early animal radiation: insights from interpreting the Cambrian problematic fossils. Front. Earth Sci. 11, 1–13. https://doi.org/10.3389/feart.2023.1120118.
      Johanson, Z., 2023. Vertebrate cranial evolution: contributions and conflict from the fossil record. Evol. Dev. 25, 119–133. https://doi.org/10.1111/ede.12422.
      Mallatt, J., 2023. Vertebrate origins are informed by larval lampreys (ammocoetes): a response to Miyashita et al. , 2021. Zool. J. Linn. Soc. 197, 287–321. https://doi.org/10.1093/zoolinnean/zlac086.
      Mikami, T., Ikeda, T., Muramiya, Y., Hirasawa, T., Iwasaki, W., 2023. Three‐dimensional anatomy of the Tully monster casts doubt on its presumed vertebrate affinities. Palaeontology 66, 1–14. https://doi.org/10.1111/pala.12646.
      Onai, T., Aramaki, T., Takai, A., Kakiguchi, K., Yonemura, S., 2023. Cranial cartilages: players in the evolution of the cranium during evolution of the chordates in general and of the vertebrates in particular. Evol. Dev. 1–12. https://doi.org/10.1111/ede.12433.
      Xiao, S., 2022. Extinctions, morphological gaps, major transitions, stem groups, and the origin of major clades, with a focus on early animals. Acta Geol. Sin. - English Ed. 96, 1821–1829. https://doi.org/10.1111/1755-6724.15027.
    2023-07-30
  • 遗迹群落指示浊流引发的海底氧化事件及其动态过程
    科研人员利用岩相和微相特征,恢复了研究层段的沉积过程;并通过遗迹学分析,识别出研究层段遗迹群落类型及其代表的相对氧含量水平。在此基础上,研究人员重建了晚二叠世上寺地区贫氧盆地内浊流沉积过程中底栖生物定殖序列及其反映的海底动态氧化过程。
      遗迹化石是指地质历史时期生物在沉积物表面或其内部产生的各种生命活动记录,包括足迹、移迹、潜穴、钻孔和其它构造(如根系内模、蛋化石和粪化石等)。由单个底栖生物群落产生的遗迹化石组合称为遗迹群落。遗迹群落是重建沉积环境、恢复古环境参数(如相对氧含量、水深、盐度等)的有力工具。然而,时间平均效应和生物潜穴间的相互穿插破坏往往为遗迹群落的识别、分析和应用带来困难。
      另外,在现代局限的贫氧盆地中,浊流是分层水体混合的普遍方式,可以显著改变深层水体的化学成分和氧含量。但在地质历史时期,浊流相关的氧化事件却很少报道。作为沉积盆地内贫氧水体氧化的一种普遍机制,浊流的作用没有得到应有的重视。
      最近,中国科学院南京地质古生物研究所晚古生代研究团队副研究员郑全锋和研究员曹长群,对四川广元上寺剖面上二叠统大隆组上段层序进行了高精度沉积学和遗迹学研究。科研人员利用岩相和微相特征,恢复了研究层段的沉积过程;并通过遗迹学分析,识别出研究层段遗迹群落类型及其代表的相对氧含量水平。在此基础上,研究人员重建了晚二叠世上寺地区贫氧盆地内浊流沉积过程中底栖生物定殖序列及其反映的海底动态氧化过程。该研究成果在线发表于地学类国际期刊《地质学杂志》(Geological Journal)。
      研究发现,研究层段主要由代表背景沉积的黑色页岩和代表快速浊流沉积的细粒浊积灰岩组成。黑色页岩中发育水平层理,生物扰动微弱,缺乏原生的生物潜穴构造(黑色页岩沉积过程中底栖生物形成的潜穴构造);指示了缺氧的海底环境。
      浊积灰岩中生物扰动强烈,发育大量原生的生物潜穴构造。依据潜穴间的截切关系和潜穴充填物特征,典型浊积灰岩中的遗迹化石可以划分为三期遗迹群落:(1)最早期的Thalassinoides/?Scolicia遗迹群落,所属分子包括Thalassinoides/?Scolicia、Zoophycos和Planolites,该遗迹群落具有最大的最大潜穴直径和最大穿透深度,代表了三个遗迹群落中最高的氧含量水平;(2)稍晚期的Planolites-Zoophycos遗迹群落,包括Planolites、Zoophycos、大型Chondrites和小型Chondrites,该遗迹群落具有中等大小的最大潜穴直径和最大穿透深度,代表了三个遗迹群落中中等水平的氧含量;(3)最晚期的Zoophycos遗迹群落,仅发育Zoophycos一个遗迹属,该遗迹群落具有最小的最大潜穴直径和最大穿透深度,以及最低的遗迹属分异度,代表了三个遗迹群落中最低的氧含量水平。其中,Thalassinoides/?Scolicia遗迹群落形成于浊流沉积的晚期和沉积后不久,指示了最为氧化的海底环境;Planolites-Zoophycos遗迹群落形成于浊流沉积之后的稍晚阶段,指示了较为还原的海底环境;Zoophycos遗迹群落形成于浊流沉积之后的更晚阶段,指示了更为还原的海底环境。
      该项研究表明,在贫氧盆地内,来自浅水区的沉积物浊流可以为深层水体带去丰富的氧气,局部性氧化贫氧的海底环境,并对底栖生物产生显著影响。
      该项研究得到了国家自然科学基金委和中国科学院战略性先导科技专项的共同资助。
      论文相关信息:Zheng, Q.F.*, Cao, C.Q., 2023. Dynamic process of turbidity current-induced benthic-marine oxygenation evidenced by sequential ichnocoenoses: An example from a Late Permian oxygen-deficient basin. Geological Journal, https://doi.org/10.1002/gj.4837.
      图1 研究层段岩相(a)、微相(b ~ f)和沉积柱状图(g)
      图2 研究层段岩石光片照片(a)及素描图(b)
      图3 研究层段沉积过程、遗迹群落定殖序列和海底氧化还原条件动态变化示意图
    2023-07-26