- Lagerstätte
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The title of this article contains the character ä. Where it is unavailable or not desired, the name may be represented as Lagerstaette.
A Lagerstätte (German: [ˈlaːɡɐʃtɛtə], from Lager 'storage' Stätte 'place'; plural Lagerstätten) is a sedimentary deposit that exhibits extraordinary fossil richness or completeness.
Palaeontologists distinguish two kinds.[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.
- Konservat-Lagerstätten (conservation Lagerstätten) are 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 where anoxic conditions, as in oxygen-free mud, has 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 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 that are not otherwise preserved in the usual shelly and bony fossil record; thus they offer a more complete record of ancient biodiversity and enable some reconstruction of the palaeoecology of ancient aquatic communities. In 1986 Simon Conway Morris calculated that 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. Lagerstatten seem to be temporally autocorrelated, perhaps because global environmental factors – perhaps climate? – affect their deposition.[3]
A number of taphonomic pathways may produce Lagerstätten. The following is an incomplete list:
- Orsten type preservation and Doushantuo type preservation preserve organisms in phosphate
- Bitter Springs type preservation preserves them in silica
- Carbonaceous films are the result of Burgess Shale type preservation
- Pyrite preserves exquisite detail in Beecher’s Trilobite type preservation
- Ediacaran type preservation preserves casts and moulds with the aid of microbial mats.
Important Lagerstätten
The world's major Lagerstätten include:
Pre-Cambrian Bitter Springs 1000–850 Ma South Australia Ediacara Hills 630-542 Ma South Australia Doushantuo Formation 600–555 Ma Guizhou Province, China Mistaken Point 565 Ma Newfoundland, Canada Cambrian Maotianshan Shales (Chengjiang) 525 Ma Yunnan Province, China Sirius Passet 518 Ma Greenland Emu Bay shale 517 Ma South Australia Kaili Formation 513–501 Ma Guizhou province, south-west China Wheeler Shale (House Range) 507 Ma Western Utah, US Burgess Shale 505 Ma British Columbia, Canada Kinnekulle Orsten and Alum Shale 500 Ma Sweden Öland Orste and Alum Shale 500 Ma Sweden Ordovician Fezouata formation c.485 Ma Draa Valley, Morocco Walcott-Rust quarry c.450 Ma New York, US Beecher's Trilobite Bed 445 Ma New York, US Soom Shale 435 Ma South Africa Silurian Wenlock Series 420 Ma England Devonian Rhynie chert 400 Ma Scotland Hunsrück Slates 390 Ma Rheinland-Pfalz, Germany Miguasha National Park 370 Ma Québec, Canada Canowindra, New South Wales 360 Ma Australia Gogo Formation 350 Ma Western Australia Carboniferous Bear Gulch Limestone 320 Ma Montana, US Joggins Fossil Cliffs 315 Ma Nova Scotia, Canada Mazon Creek 300 Ma Illinois, US Montceau-les-Mines 300 Ma France Hamilton Quarry 295 Ma Kansas, US Triassic Madygen Formation 230 Ma Kyrgyzstan Ghost Ranch 205 Ma New Mexico, US Jurassic Holzmaden/Posidonia Shale 180 Ma Württemberg, Germany Karabastau Formation 155.7 Ma France La Voulte-sur-Rhône 160 Ma Ardèche, France Solnhofen limestone 145 Ma Bavaria, Germany Canjuers limestone 145 Ma France Cretaceous Yixian Formation ca 125-121 Ma Liaoning, China Las Hoyas ca 125 Ma (Barremian) Cuenca, Spain Crato Formation ca 117 Ma (Aptian) northeast Brazil Xiagou Formation ca 110 Ma Gansu, China Haqel/Hadjula/al-Nammoura lagerstätten ca 95 Ma Lebanon Santana Formation 108–92 Ma Brazil Smoky Hill Chalk 87–82 Ma Kansas and Nebraska, US Ingersoll Shale 85 Ma Alabama, US Auca Mahuevo 80 Ma Patagonia, Argentina Zhucheng 65 Ma Shandong, China Eocene Fur Formation 55–53 Ma Fur, Denmark London Clay 54–48 Ma UK Green River Formation 50 Ma Colorado/Utah/Wyoming, US Monte Bolca 49 Ma Italy Messel Oil Shale 49 Ma Hessen, Germany Oligocene–Miocene Dominican amber 30–10 Ma Dominican Republic Riversleigh 25–15 Ma Queensland, Australia Miocene Clarkia fossil beds 20–17 Ma Idaho, US Barstow Formation 13.4 Ma California, US Ashfall Fossil Beds 10 Ma Nebraska, US Pleistocene The Mammoth Site 26 ka South Dakota, US Rancho La Brea Tar Pits 40 ka - 12 ka California, US See also
- List of fossil sites (with link directory)
References
- ^ The term was originally coined by Adolf Seilacher here:Seilacher, A. (1970). "Begriff und Bedeutung der Fossil-Lagerstätten: Neues Jahrbuch fur Geologie und Paläontologie" (in German). Monatshefte 1970: 34–39.
- ^ Briggs et al. 1983; Aldridge et al. 1993.
- ^ Retallack, G. J. (2011). "Exceptional fossil preservation during CO2 greenhouse crises?". Palaeogeography, Palaeoclimatology, Palaeoecology. doi:10.1016/j.palaeo.2011.04.023.
- Penney, D.(ed.) 2010. Biodiversity of Fossils in Amber from the Major World Deposits. Siri Scienfic Press, Manchester, 304 pp.
- "Fossil Lagerstätten". Department of Earth Sciences, University of Bristol. 2003. http://palaeo.gly.bris.ac.uk/Palaeofiles/Lagerstatten/. Retrieved 2005-11-21. — A catalogue of sites of exceptional fossil preservation produced by MSc palaeobiology students at University of Bristol's Department of Earth Sciences.
- Orr, Patrick J.; Derek E. G. Briggs, David J. Siveter and Derek J. Siveter (1 January 2000). "Three-dimensional preservation of a non-biomineralized arthropod in concretions in Silurian volcaniclastic rocks from Herefordshire, England". Journal of the Geological Society 157 (1): 173–186. doi:10.1144/jgs.157.1.173. http://jgs.geoscienceworld.org/cgi/content/abstract/157/1/173. Retrieved 2006-10-26.
Categories:- Paleontology
- Fossils
- Lagerstätten
- German words and phrases
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