What is Lagerstätten?
[[File:Diplomystus dentatus Green River Formation Wyoming.jpg|thumb|''Diplomystus dentatus'' from the [[Green River]] Formation, an [[Eocene]] Lagerstätte]] [[File:Marella.png|thumb|220px|''[[Marrella]]'', the most abundant [[Burgess Shale]] organism]] '''Lagerstätte''' (plural: ''Lagerstätten'') is a [[German language|German]] word for places (sites) of exceptional [[fossil]] preservation. Adolf Seilacher coined the term in 1970 to describe sites, like [[Solnhofen limestone|Solnhofen]], which yielded the most exceptional fossils.<ref>Seilacher A. 1970. Begriff und Bedeutung der Fossil-Lagerstätten: Neues Jahrbuch fur Geologie und Paläontologie. ''Monatshefte'' 1970: 34–39.</ref> Extra-special sites are called ''Konservat-Lagerstätten'' (conservation Lagerstätten). These are deposits known for the exceptional preservation of fine details. There [[skeleton]]s are mostly articulated (bones together in life form), and the soft parts are preserved as impressions or [[casting|casts]]. == Preservation == In Lagerstätten the normal processses of [[decay]] after death were less active or halted as [[sediment]] was deposited. This allowed the preservation of soft parts and exceptional detail. There are several possible causes which allow this to happen: #[[Anoxic]] or near anoxic conditions (e.g. [[oxygen]]-free [[mud]]) which suppresses common [[bacteria]]l decomposition long enough for the initial casts of soft body parts to register. #Rapid [[burial]] in [[Tuff|volcanic ash]] from a nearby eruption. This prevents [[scavenger]]s and [[burrow]]ing animals from reaching the dead body. It also produces a low-oxygen environment. #Rapid burial by mud-slides. #High [[Salinity|salt content]] in the water, which few organisms can live in. This condition occurred in the lagoons which produced the [[Solnhofen limestone]]. In these conditions, which are exceptional, [[scavenger]]s, [[burrower]]s and [[bacteria]] are eliminated or reduced. Then the normal processes of deposition and fossilisation produces [[strata]] containin