What is Solnhofen Limestone?
[[File:Solnhofen Rhamphorhynchus cast.jpg|thumb|right|230px|''[[Rhamphorhynchus]]'' from Solnhofen]] The '''Solnhofen limestone''' is the world's most famous fossil site. It is a [[lagerstätte]] of Upper [[Jurassic]] [[limestone]] which has preserved many fossils in great detail. The specimens of ''[[Archaeopteryx]]'' are perhaps the world's most valuable fossils, because they are the earliest fossils of a bird capable of flight. The Solnhofen beds lie in the [[Germany|German]] state of [[Bavaria|Bavaria (Bayern)]], halfway between [[Nuremberg|Nuremberg (Nürnberg)]] and [[Munich|Munich (München)]]. They were originally [[Quarry|quarried]] as a source of roof and floor [[tile]]s, then for [[lithography|lithographic]] [[printing]]. == Paleoenvironment == In the late Jurassic this area was an [[archipelago]] at the edge of the [[Tethys Sea]]. This included placid [[lagoon]]s which had limited access to the open sea because they were surrounded by [[coral reef]]s. Water runoff from the land was low and, under the sun, [[evaporation]] was high. [[Salinity]] rose so high that the resulting [[brine]] could not support life, except at the top of the water column.<ref name=Blick/> The lowest water was not only very salty, but [[hypoxic]]: very low in [[oxygen]]. This was caused by the lack of water mixing. Many ordinary [[scavenger]]s were absent from the lagoon floor. From the condition of the water, it follows that almost all of the fossilised animals were not living in the lagoon.<ref name=Blick/> They must have lived on land, in the air, or out to sea beyond the reef. Then when they died, they fell, drifted, or were washed into the lagoons from the air, ocean or land. Occasional storms at sea would have killed flying animals, and swept fish over the reef in a suspension of finely-dispersed [[lime]]. There the bodies sank into the dead zone and were preserved. Once in the lagoon, bodies became buried in soft [[carbonate]] mud. Thus, many delicate creatures avoided consumption by scavengers or being torn apart by c