Lagerstätte

Fossil fish from the Green River Formation, an Eocene Lagerstätte
Stranded scyphozoans with Climactichnites trackways from Blackberry Hill, Wisconsin (Cambrian). Scyphozoan in foreground is 10 cm in diameter. Slab is in hyporelief.

A Lagerstätte (German: [ˈlaːɡɐˌʃtɛtə], from Lager 'storage, lair' Stätte 'place'; plural Lagerstätten) is a sedimentary deposit that exhibits extraordinary fossils with exceptional preservation—sometimes including preserved soft tissues. These formations may have resulted from carcass burial in an anoxic environment with minimal bacteria, thus delaying decomposition. Lagerstätten span geological time from the Neoproterozoic era to the present. Worldwide, some of the best examples of near-perfect fossilization are the Cambrian Maotianshan shales and Burgess Shale, the Devonian Hunsrück Slates and Gogo Formation, the Carboniferous Mazon Creek, the Jurassic Solnhofen limestone, and the Cretaceous Santana and Yixian formations.

Types

Palaeontologists distinguish two kinds:[1]

  1. Konzentrat-Lagerstätten (concentration Lagerstätten) are deposits with a particular "concentration" of disarticulated organic hard parts, such as a bone bed. These Lagerstätten are less spectacular than the more famous Konservat-Lagerstätten. Their contents invariably display a large degree of time averaging, as the accumulation of bones in the absence of other sediment takes some time. Deposits with a high concentration of fossils that represent an in situ community, such as reefs or oyster beds, are not considered Lagerstätten.
  2. Konservat-Lagerstätten (conservation Lagerstätten) are deposits known for the exceptional preservation of fossilized organisms or traces. The individual taphonomy of the fossils varies with the sites. Conservation Lagerstätten are crucial in providing answers to important moments in the history and evolution of life. For example, the Burgess Shale of British Columbia is associated with the Cambrian explosion, and the Solnhofen limestone with the earliest known bird, Archaeopteryx.

Preservation

Konservat-Lagerstätten preserve lightly sclerotized and soft-bodied organisms or traces of organisms that are not otherwise preserved in the usual shelly and bony fossil record; thus, they offer more complete records of ancient biodiversity and behavior and enable some reconstruction of the palaeoecology of ancient aquatic communities. In 1986, Simon Conway Morris calculated only about 14% of genera in the Burgess Shale had possessed biomineralized tissues in life. The affinities of the shelly elements of conodonts were mysterious until the associated soft tissues were discovered near Edinburgh, Scotland, in the Granton Lower Oil Shale of the Carboniferous.[2] Information from the broader range of organisms found in Lagerstätten have contributed to recent phylogenetic reconstructions of some major metazoan groups. Lagerstätten seem to be temporally autocorrelated, perhaps because global environmental factors such as climate might affect their deposition.[3]

A number of taphonomic pathways may produce Lagerstätten. The following is an incomplete list:

Important Konservat-Lagerstätten

The world's major Lagerstätten include:

Precambrian
    Bitter Springs 1000–850 Mya South Australia
    Doushantuo Formation 600–555 Mya Guizhou Province, China
    Mistaken Point 565 Mya Newfoundland, Canada
    Ediacara Hills 550-545? Mya South Australia
Cambrian
    Maotianshan Shales (Chengjiang) 515 Mya Yunnan Province, China
    Sirius Passet 518 Mya Greenland
    Emu Bay Shale 513 Mya South Australia
    Kaili Formation 513–501 Mya Guizhou province, south-west China
    Blackberry Hill ~510–500 Mya Central Wisconsin, US
    Wheeler Shale (House Range) 507 Mya Western Utah, US
    Burgess Shale 508 Mya British Columbia, Canada
    Kinnekulle Orsten and Alum Shale 500 Mya Sweden
Ordovician
    Fezouata Formation about 485 Mya Draa Valley, Morocco
    Beecher's Trilobite Bed 460? Mya New York, US
    Walcott-Rust Quarry about 455? Mya New York, US
    Soom Shale 450? Mya South Africa
Silurian
    Wenlock Series ~425 Mya England, UK
Devonian
    Rhynie chert 400 Mya Scotland, UK
    Hunsrück Slates (Bundenbach) 390 Mya Rheinland-Pfalz, Germany
    Gogo Formation 380 Mya (Frasnian) Western Australia
    Miguasha National Park 370 Mya Québec, Canada
    Canowindra, New South Wales 360 Mya Australia
Carboniferous
    Bear Gulch Limestone 320 Mya Montana, US
    Joggins Fossil Cliffs 315 Mya Nova Scotia, Canada
Linton Diamond Coal Mine 312 Mya Ohio, US
    Mazon Creek 310 Mya Illinois, US
    Montceau-les-Mines[4][5] 300 Mya France
    Hamilton Quarry 300 Mya Kansas, US
Permian
    Mangrullo Formation[6] about 285-275 Mya (Artinskian) Uruguay
Triassic
    Madygen Formation 230 Mya Kyrgyzstan
    Ghost Ranch 205 Mya New Mexico, US
Jurassic
    Holzmaden/Posidonia Shale 180 Mya Württemberg, Germany
    Mesa Chelonia[7] 164.6 Mya Shanshan County, China
    La Voulte-sur-Rhône 160 Mya Ardèche, France
    Karabastau Formation 155.7 Mya Kazakhstan
    Solnhofen Limestone 145 Mya Bavaria, Germany
    Canjuers Limestone 145 Mya France
Cretaceous
    Las Hoyas about 125 Mya (Barremian) Cuenca, Spain
    Yixian Formation about 125-121 Mya Liaoning, China
    Xiagou Formation about 120-115? Mya (mid-Apt.) Gansu, China
    Crato Formation about 117 Mya (Aptian) northeast Brazil
    Haqel/Hadjula/al-Nammoura about 95 Mya Lebanon
    Santana Formation 108-92 Mya Brazil
    Smoky Hill Chalk 87-82 Mya Kansas and Nebraska, US
    Ingersoll Shale 85 Mya Alabama, US
    Auca Mahuevo 80 Mya Patagonia, Argentina
    Zhucheng 66 Mya Shandong, China
Eocene
    Fur Formation 55-53 Mya Fur, Denmark
    London Clay 54-48 Mya England, UK
    McAbee Fossil Beds 52.9 ± 0.83 Mya British Columbia, Canada
    Green River Formation 50 Mya Colorado/Utah/Wyoming, US
    Klondike Mountain Formation 49.4 ± .5 Mya Washington, US
    Monte Bolca 49 Mya Italy
    Messel Oil Shale 49 Mya Hessen, Germany
    Quercy Phosphorites Formation[8] 25–45 Mya South-Western France
OligoceneMiocene
    Dominican amber 30-10 Mya Dominican Republic
    Riversleigh 25-15 Mya Queensland, Australia
Miocene
    Clarkia fossil beds 20-17 Mya Idaho, US
    Barstow Formation 19-13.4 Mya California, US
    Ashfall Fossil Beds 12–13? Mya Nebraska, US
Pleistocene
    Mammoth Site 26 Kya South Dakota, US
    Rancho La Brea Tar Pits 40-12 Kya California, US
    Waco Mammoth National Monument 65-51 Kya Texas, US
    El Breal de Orocual 2.5-1 Mya. Monagas, Venezuela
    El Mene de Inciarte 25.5-28 Kya Zulia, Venezuela

See also

References

  1. The term was originally coined by Adolf Seilacher here:Seilacher, A. (1970). "Begriff und Bedeutung der Fossil-Lagerstätten: Neues Jahrbuch fur Geologie und Paläontologie". Monatshefte (in German). 1970: 34–39.
  2. Briggs et al. 1983; Aldridge et al. 1993.
  3. Retallack, G. J. (2011). "Exceptional fossil preservation during CO2 greenhouse crises?". Palaeogeography, Palaeoclimatology, Palaeoecology. doi:10.1016/j.palaeo.2011.04.023.
  4. Garwood, Russell J.; Sharma, Prashant P.; Dunlop, Jason A.; Giribet, Gonzalo (2014). "A Paleozoic Stem Group to Mite Harvestmen Revealed through Integration of Phylogenetics and Development". Current Biology. 24 (9): 1017–1023. doi:10.1016/j.cub.2014.03.039. Retrieved April 17, 2014.
  5. Perrier, V.; Charbonnier, S. (2014). "The Montceau-les-Mines Lagerstätte (Late Carboniferous, France)". Comptes rendus Palevol. 13 (5): 353–367.
  6. Piñeiro, G.; Ramos, A.; Goso, C. S.; Scarabino, F.; Laurin, M. (2012). "Unusual Environmental Conditions Preserve a Permian Mesosaur-Bearing Konservat-Lagerstätte from Uruguay". Acta Palaeontologica Polonica. 57 (2): 299. doi:10.4202/app.2010.0113.
  7. Wings, Oliver; Rabi, Márton; Schneider, Jörg W.; Schwermann, Leonie; Sun, Ge; Zhou, Chang-Fu; Joyce, Walter G. (2012), "An enormous Jurassic turtle bone bed from the Turpan Basin of Xinjiang, China", Naturwissenschaften: The Science of Nature, 114, doi:10.1007/s00114-012-0974-5
  8. Lalloy, F.; Rage, J.-C.; Evans, S.E.; Boistel, R.; Lenoir, N.; Laurin, M. (2013). "A re-interpretation of the Eocene anuran Thaumastosaurus based on microCT examination of a 'mummified' specimen". PLoS ONE. 8: 1–11. doi:10.1371/journal.pone.0074874.

Further reading

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