What is Upper Jurassic?
[[File:Bats head from white nothe.jpg|thumb|right|The cliff forming Purbeck limestone from the Upper Jurassic at [[Bat's Head]], [[Dorset]], [[United Kingdom|UK]].]] The '''Upper Jurassic''' is the last [[geology|geological]] [[Epoch (geology)|epoch]] in the [[Jurassic]] that began 163.5 [[million]] years ago (mya), and ended at 145 mya. It was followed by the [[Lower Cretaceous]]. ==Paleogeography== During the Upper Jurassic epoch, [[Pangaea]] broke up into two [[supercontinent]]s, [[Laurasia]] to the north, and [[Gondwana]] to the south. The result of this break-up was the spawning of the [[Atlantic Ocean]]. However, at this time, the Atlantic Ocean was relatively narrow. [[Sea level]] was high, though not so high as during the [[Upper Cretaceous]]. The [[Laurasia]]n landmass was broken up by the rising sea into large islands. The rocks were [[carbonate]] [[limestone]]s and [[clay]]s. The epoch included the famous [[Solnhofen limestone]] [[lagerstätte]], where ''[[Archaeopteryx]]'' was found. == Organic productivity == The Upper Jurassic of England and Europe bears a huge amount of the products of life. The [[Kimmeridge clay]] is the main source for the huge [[North Sea]] [[oil]] reserves, and the whole epoch is stuffed full of [[Ocean|marine]] [[fossil]]s. Many [[dinosaur]] remains have also been found. The epoch starts with the Oxford Clay deposited in a shallow seaway of 10 to 50 metres depth.<ref> Tang C.M. 2002. Oxford Clay: England's Jurassic Marine Park, in Bottjer, Etter, Hagadorn & Tang ''Exceptional fossil preservation''. Columbia N.Y.</ref> The first fossils which show small dinosaurs with [[feather]]s are found: ''[[Anchiornis]]''. == Related pages == *[[Blue Lias]] *[[Lower Jurassic]] *[[Middle Jurassic]] *[[Jurassic]] == References == {{Reflist}} {{Geologic History}} {{DEFAULTSORT:Jurassic, Upper}} [[Category:Jurassic]]