Taphonomy of fish concentrations from the Upper Jurassic Solnhofen Plattenkalk of Southern Germany
Taphonomy of fish concentrations from the Upper Jurassic Solnhofen Plattenkalk of Southern Germany
复制标题
德国南部上侏罗统Solnhofen Plattenkalk 鱼类浓度的埋藏学
DOI：
10.1127/njgpa/2019/0809
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发表时间：
2019-04
期刊：
影响因子：
--
通讯作者：
Hu Liang
中科院分区：
文献类型：
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作者：
Pan Yanhong;FRANZ T. FÜRSICH;PATRICK CHELLOUCHE;Hu Liang
在形成Solnhofen化石Lagerstatte的上侏罗世的plattenkalks中，层面上脊椎动物化石的密度通常很低。然而，在一些层面上，存在大量集中的小鳞藓（布兰维尔，1818年）。本文的目的是从埋藏学的角度分析和解释这些f-sh浓度。为此，本文对L.对三个大平板上的Sprattiformis浓度进行了半定量分析。层面上的个人的浓度被解释为记录当地的大规模死亡事件所造成的热带风暴，短时间内，中断的密度跃层分离hypersaline，缺氧的底部沃茨从正常的海洋表面沃茨在Plattenkalk盆地。大规模的死亡是由手足抽搐的特点，如张开的下巴，超伸的鳃蒂射线，和张开的鳍，这发生在大多数标本的支持。一般来说，良好的保存fsh是由于缺乏死后化石，快速掩埋和/或微生物的过度生长，以及密度跃层的快速重建与不适宜居住的条件上的盆地floo。脊椎骨的死后凹陷和脊柱的各种移位最有可能分别由软组织的不同衰变阻力和体腔内衰变气体的压力引起。f sh浓度的埋藏分析可以提供非常详细的古环境信息，并作为古环境重建的独立证据，补充地球化学和沉积数据。
The density of vertebrate fossils on bedding planes is generally very low in the Upper Jurassic plattenkalks forming the Solnhofen fossil Lagerstatte. There are, however, a few bedding planes where large concentrations of the small fis Leptolepides sprattiformis (BLAINVILLE, 1818) occur. The aim of this paper is to analyse and interpret these f sh concentrations from a taphonomic point of view. For this purpose, the taphonomic features of L. sprattiformis concentrations on three large slabs were semi-quantitatively analysed. The concentrations of individuals on bedding planes are explained as recording local mass mortality events caused by tropical storms that, for short intervals, disrupted the pycnocline which separated hypersaline, oxygen-poor to anoxic bottom waters from normal marine surface waters in the Plattenkalk basins. Mass mortality is supported by tetany features such as gaping jaws, hyperextended branchiostegal rays, and splayed f ns, which occur in the majority of the specimens. The generally excellent preservation of the f sh resulted from lack of postmortem f oatation, rapid burial and/or overgrowth by microbial f lms, and quick re-establishment of the pycnocline with inhospitable conditions on the basin floo. The post-mortem concave-arching of the backbones and various displacements of the vertebral column were most likely caused by varying decay resistance of soft tissues and the pressure of decay gases in the body cavities, respectively. The taphonomic analysis of f sh concentrations can provide very detailed palaeoenvironmental information and serves as an independent line of evidence for palaeoenvironmental reconstructions that complements geochemical and sedimentary data.