MarÃlia Formation
The Marília Formation is a sequence of continental sedimentary rocks of the Upper Cretaceous, which is open in southern Brazil. It belongs to the Bauru Group and is located in the Paraná Basin. Famous is this lithostratigraphic formation for their vertebrate fossils, which include among others the remains of dinosaurs with. The formation is divided into three units ( Subformationen ) - in the Echaporã Members, the Serra da galga Members and the Ponte Alta Member. In the south, São José do Rio Preto lineup borders.
In the rocks of the formation are mostly coarse -grained to conglomeratic sandstones, siltstones and clayey layers of carbonate. The climate at the time of the deposits was hot and dry. Long dry periods were interrupted by periodic heavy rains which formed temporary lakes. The deposits come from alluvial fans, alluvial plains, as well as the short-lived lakes.
The formation is dated to the Maastrichtian, based on fossils of ostracods and charophyte ( biostratigraphy ).
Fossil content
For its wealth of fossils celebrated in particular the reference Peirópolis is near the city of Uberaba in the Brazilian state of Minas Gerais. This deposit has been known since 1920, but has been studied only in 1947 with the field studies of paleontologist Llewellyn Ivor Price thorough scientific. Vertebrate fossils include fish, the frog Baurubatrachus, the lizard Pristiguana, the turtle Cambaremys, the crocodiles Itasuchus, Peirosaurus and Uberabasuchus and theropod and sauropod dinosaur with a: theropods are represented by remains of Abelisauriden, Carcharodontosauriden and Maniraptoren while sauropods by the Titanosaurier Baurutitan, Trigonosaurus, Uberabatitan and Aeolosaurus are represented.