| Modes of preservation: | body,mold/impression,trace,soft parts,recrystallized,original calcite,replaced with calcite,replaced with pyrite,replaced with phosphate |
| Lagerstätten type: | conservation |
| Size of fossils: | macrofossils,mesofossils,microfossils |
| Spatial orientation: | random |
| Preservation of anatomical detail: | excellent |
| Abundance in sediment: | abundant |
| Articulated whole bodies: | many |
| Associated major elements: | many |
| Disassociated major elements: | many |
| Disassociated minor elements: | many |
| Fragmentation: | occasional |
| Temporal resolution: | snapshot |
| Spatial resolution: | parautochthonous |
Taphonomy comments: Vertebrates: "The vertebrate assemblage consists of complete and disarticulated specimens, as well as primary fragments of vertebral columns, single isolated bones, scales, etc. They seem to be randomly distributed in the sediment. Skeletons are embedded laterally, sometimes in dorsoventral position. Many skeletons of our collection are fully articulated, and disarticulated skeletal elements of fishes and other vertebrates appear to be a result of decay during post-mortem floating. At present there is no evidence for major current transport on the sea floor. Most vertebrate fossils are compressed, as a consequence of the compaction of the sediment. Some specimens are preserved in 3D, although flattened. In several of these specimens, geopetal collapse is observed. In general, compressed specimens are embedded parallel to the lamination. Delicate morphological elements (e.g., fin rays, gill rakers and filaments) of some specimens are obliquely embedded, indicating that the sediment must have been soft. According to microprobe analysis, bones are frequently preserved as fluorapatite. Phosphatization of soft parts such as intestinal contents, myotomes, gill filaments, cycloid scales and fins of fishes, is observed occasionally and indicates that replacement of organic tissues by fluorapatite occurred at a very early stage of diagenetic mineralization, preceding or accompanying microbial decay, and often prior to sediment compaction. This process of a very early and almost instantaneous phosphatization has been described as a medusa effect by Martill (1993a)."
Invertebrates: Ammonoids are preserved as compressed internal moulds. Most are embedded laterally in the sediment, but occasional diagonally or vertically embedded specimens also occur and suggest the presence of soft or soupy sediment. Aptychi are mostly found isolated; in rare cases, they still rest in the living chamber. Our collection also includes specimens with a phosphatic preservation of the sipho, either complete or with different degrees of fragmentation. Most inoceramids still preserve their thick prismatic shells, although the aragonitic layer is always recrystallized. In a few specimens, the shell is replaced by goethite indicating very early diagenetic replacement of the periostracum by pyrite. Most inoceramid shells are closed, although separated valves, fragmented shells, or rarely shell hash also occur. Calcitic shells such as oysters, ammonoid aptychi, or foraminiferal tests, are preserved with minor recrystallization. Phosphatization of the invertebrate fossils has been recognized in rare occasions, for instance in decapod crustacean carapaces or ammonite siphos."
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