A preserved Eocene coastline and seabed, complete with amazing fossils…Every now and again th

A preserved Eocene coastline and seabed, complete with amazing fossils…Every now and again the vagaries of geological history bequeath us a snapshot in time, when a particular set of circumstances (unique in each case) created perfect preservation conditions for fossilised organisms. Now known to palaeontologists as lagerstatte and prized for the well resolved snapshots of past ecosystems that they provide (many preserve soft parts as well), their products grace museums and cabinets of curiosities worldwide.One of the first discovered by Europeans is Monte Bolca in Italy (at least 11th century CE), where a chunk of the Tethys Ocean that once separated Africa and Europe along with its attendant coastline was deposited some 49 million years ago, before being uplifted in two phases culminating some 24 million years ago. The rocks in these new hills, the result of the compressional stress from Africa’s collision with Eurasia) are limestones with the odd layer of dark shale in a fossil rich section 20 metres thick. While the fish (whose internal organs and original colours are often fossilised) are the most famous finds, land animals including snakes have turned up as well. The name strictly refers to one small quarry known as Pesciara (fishbowl), but has also been applied to the same biota found in other pockets elsewhere in the region.The area was lucky, in that oxygen levels were low during sedimentation, ensuring that decay was held at bay long enough for the fine grained limey mud to replace the tissues before solidifying into rock over the aeons since. In addition to fish (over 250 species) and snakes, jellyfish, crustaceans (the crab and lobster family) and worms have turned up, along with insects and land plants, feathers and tortoise shell plates. They are the earliest tropical marine fossil fish assemblage after the end Cretaceous mass extinction 65 million years ago, providing an important link between the two very different worlds. All the fish species are extinct, but many closely resemble their still living descendants.Fossils from this site are considered national treasures, and the main quarry has been owned by the same family for 4 centuries. There are several fossil rich horizons, and workers tunnel down dip into the hill to mine them. Kings have collected them, Louis Agassiz the man who gave us the ice ages) studied them in his compendious multivolume work on fossil fishes helping lay the groundwork that would later help support the theory of evolution…all in all this place had an important part to play in the history of earth and Life sciences both.LozImage credit: Long primitive swordfish (Blochius longirostris): Haplochromis, fossil snake: Raimond Spekkinghttp://bit.ly/28QAl6uhttp://bit.ly/28Tesrvhttp://bit.ly/28POCiZhttp://bit.ly/28S0uGO -- source link
Tumblr Blog : the-earth-story.com

More pics about