Kaili Formation

The Kaili Formation, ranging from the late Lower Cambrian to early Middle Cambrian, contains an early Middle Cambrian Konservat Lagerstätte with many well-preserved fossils known collectively as the Kaili Biota. Named for nearby city of Kaili in the Guizhou province of southwest China, the Kaili formation is more than 200 meters thick with boundaries dated from the early to the early-middle Cambrian (513 to 501 million years ago). This age places it between the two most important and famous Cambrian Lagerstätten: the Burgess Shale and the Maotianshan Shale (containing the Chengjiang Biota).

Fossils

The faunal assemblage is highly diverse, comprising some 110 genera among 11 phyla; of these, some 40 genera are also found in the Burgess Shale, and some 30 are also found in the Maotianshan Shale. Trilobites and eocrinoids with hard parts that are easily preserved are the most common fossils, but many animals with only soft tissues are also preserved. For example, an arthropod similar to the Ediacaran biota Parvancorina of the Neoproterozoic age Ediacara Hills of South Australia has been found at the Kaili site.^[1] Some other notable fossils discovered at Kaili are putative invertebrate eggs and embryos^[2], trace fossils of the genus Gordia^[3], naraoiids, chancellorids, and Marrella.

Depositional setting

The deposittional environment of the Kaili formation is not entirely known, and there are two hypotheses for its formation. It may have been a nearshore marine environment with 'normal' levels of oxygenation; or it may have been a deeper water environment further from the shore, on the open continental shelf; in this setting oxygen would not be available below the surface layers of the deposited sediment.^[3] The trace fossil assemblages in the formation suggest that it was below wave base and reasonably well oxygenated.^[3]

References

^ Attention: This template ({{cite doi}}) is deprecated. To cite the publication identified by doi: 10.1080/08912960500508689 , please use {{cite journal}} (if it was published in a bona fide academic journal, otherwise {{cite report}} with |doi= 10.1080/08912960500508689 instead.
^ Lin, J.; et al. (2006). "Silicified egg clusters from a Middle Cambrian Burgess Shale–type deposit, Guizhou, south China". Geology. 34 (12): 1037–1040. {{cite journal}}: Explicit use of et al. in: |author= (help)CS1 maint: extra punctuation (link)
^ ^a ^b ^c Attention: This template ({{cite doi}}) is deprecated. To cite the publication identified by doi:10.1016/j.palaeo.2009.02.017, please use {{cite journal}} (if it was published in a bona fide academic journal, otherwise {{cite report}} with |doi=10.1016/j.palaeo.2009.02.017 instead.

[Lin2006-1] Attention: This template ({{cite doi}}) is deprecated. To cite the publication identified by doi: 10.1080/08912960500508689 , please use {{cite journal}} (if it was published in a bona fide academic journal, otherwise {{cite report}} with |doi= 10.1080/08912960500508689 instead.

[2] Lin, J.; et al. (2006). "Silicified egg clusters from a Middle Cambrian Burgess Shale–type deposit, Guizhou, south China". Geology. 34 (12): 1037–1040. {{cite journal}}: Explicit use of et al. in: |author= (help)CS1 maint: extra punctuation (link)

[Wang2009-3] Attention: This template ({{cite doi}}) is deprecated. To cite the publication identified by doi:10.1016/j.palaeo.2009.02.017, please use {{cite journal}} (if it was published in a bona fide academic journal, otherwise {{cite report}} with |doi=10.1016/j.palaeo.2009.02.017 instead.

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