Taphonomy of the Lower Permian Geraldine Bonebed in Archer County, Texas
Taphonomy of the Lower Permian Geraldine Bonebed in Archer County, Texas
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DOI：
10.1016/0031-0182(87)90051-4
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发表时间：
1987
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影响因子：
--
通讯作者：
P. Sander
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文献类型：
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作者：
P. Sander
德克萨斯州北部的下二叠统海军上将组红床以其脊椎动物群而闻名。本文对德克萨斯州阿彻县中部的杰拉尔丁骨床进行了详细的埋藏学分析，该骨床是该地区最重要的脊椎动物化石产地之一。杰拉尔丁骨床位于小型蜿蜒河流系统的洪泛盆地相（红色和灰色泥岩，含有丰富的 Psaronius 根）。这些盆地覆盖着茂密的沼泽森林，脊椎动物种类繁多。杰拉尔丁骨床 (Geraldine Bonebed) 在 30 平方米的面积内出土了 44 个四足动物属的部分关节骨骼以及另外 8 个脊椎动物类群的遗骸。这些骨头躺在一层蕨类植物、针叶树叶子和混有木炭化石的木材上。沉积物、“Wasseleichen”的出现以及骨骼方向表明死后在水中的运输和沉积。一次大规模死亡事件（可能是森林火灾）将动物驱赶到池塘中并在那里死亡。漂浮在水中的尸体与植物碎片一起被风引起的漂流集中到这个特殊的化石沉积物中。来自德克萨斯州墨西哥湾沿岸的 Weigelt (1927) 描述了大规模死亡后骨床形成过程的一个最新例子。
Lower Permian Admiral Formation redbeds in north Texas are famous for their vertebrate fauna. This paper provides a detailed taphonomic analysis of the Geraldine Bonebed in central Archer County, Texas, one of the most important fossil vertebrate occurrences in the region.The Geraldine Bonebed is situated in the floodbasin facies (red and gray mudstones with abundantPsaroniusroots) of a small meandering river system. Such basins were covered with a dense swamp forest with a high diversity of vertebrates. The Geraldine Bonebed has yielded, from an area of 30 m2, 44 partly articulated skeletons of four genera of tetrapods and the remains of another eight vertebrate taxa. The bones lie on a layer of fern, and conifer foliage and wood intermingled with fossil charcoal. The sediment, the occurrence of “Wasserleichen”, and the skeleton orientation indicate post-mortem transportation and deposition in water.A single mass death event, which could have been a forest fire, drove the animals into a pond where they perished. Carcasses floating in water together with plant debris were concentrated by wind-induced drift into this exceptional fossil deposit. A recent example of this process of bonebed formation after mass death was described by Weigelt (1927) from the Texas Gulf Coast.