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LagerstttenLagerstätten (German, singular: Lagersttte, literally: place(s) of storage ) are sedimentary deposits that exhibit extraordinary fossil richness or completeness. The German word literally translates as "resting places." Palaeontologists distinguish two kinds: Konzentrat-Lagersttten (or concentration Lagersttten) signifies deposits with a particular concentration of disarticulated organic hard parts, such as a bone bed or an oyster bed. These concentration Lagersttten are less spectacular than the more famous Konservat-Lagersttten (or conservation lagersttten), deposits known for the exceptional preservation of fossilized organisms, where the soft parts are preserved in the form of impressions or casts. This is caused by incompleteness of biological recycling, for example anoxic conditions, as in oxygen-free mud, have suppressed common bacterial decomposition long enough for the initial casts of soft body parts to register (the individual taphonomy of the fossils varies with the sites). Conservation Lagersttten are crucial in providing answers to important moments in the history and evolution of life, for example the Burgess Shale is associated with the Cambrian explosion, and the Solnhofen limestone with the earliest known bird, Archeopteryx. Important Lagersttten Some of the world's major Lagerstätten include: - Ediacara Hills; 700 mya; South Australia
- Doushantuo Formation; 600-555 mya: Guizhou Province, China
- Chenjiang fauna in the Maotianshan shales; 518 mya: Yunnan Province, China
- Sirius Passet; 518 mya; Greenland
- Burgess Shale; 505 mya ; British Columbia, Canada
- 'Orsten'; 500 mya; Sweden
- Wenlock Limestone of Dudley; 420 mya; England
- Rhynie Chert; 400 mya; Scotland
- Hunsrück Slates; 390 mya; Rheinland-Pfalz, Germany
- Hamilton Quarry; 320 mya; Kansas, US
- Mazon Creek; 300 mya; Illinois, US
- Karatau; 213 - 144 mya; Kazakhstan
- Holzmaden; 190 mya; Württemberg, Germany
- La Voulte-sur-Rhone; 160 mya; France
- Solnhofen limestone; 145 mya; Bavaria, Germany
- Chaomidianzi Formation = Yixian Formation; ca 135 mya; Liaoning, China
- Crato Formation; Early Cretaceous (Aptian), ca 117 mya; northeast Brazil
- Santana Formation; 108 - 92 mya; Brazil
- Green River Formation; 50 mya; Colorado/Utah/Wyoming
- Monte Bolca; 49 mya; Italy
- Messel Oil Shale; 49 mya; Hessen, Germany
- Dominican amber; 10 - 30 mya; Dominican Republic
- Ashfall Fossil Beds; 10 mya; Nebraska, United States
- Rancho La Brea Tar Pits; 20,000 yrs bp; California, United States
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