Juréia Formation
Etymology
The formation is named after the Jureia-Itatins Ecological Station, São Paulo.
Description
![](http://upload.wikimedia.org/wikipedia/commons/thumb/7/7e/Turbidite_formation.jpg/330px-Turbidite_formation.jpg)
The Jureia Formation is 952 to 2,000 metres (3,123 to 6,562 ft) thick, and includes a succession of clastics between the coarse facies of the Santos Formation in the western proximal part and the fine-grained clastics of the Itajai-Açu Formation in the eastern distal part of the Santos Basin. The formation is characterized by dark grey to greenish and brown shales, dark grey siltstones, fine-very fine sandstones and light ochre calcisilts. The depositional environment is thought to be of a marine platform setting as pro-delta facies on the shelf edge. The age based on palynomorphs and calcareous nannofossils is Late Cretaceous (Santonian-Maastrichtian). Two new ostracod species were identified in the drilling cuttings of wells drilled into the Santonian-Campanian section, ?Afrocytheridea cretacea and Pelecocythere dinglei.
The formation is the reservoir rock of the Merluza Field, the first discovery in 1979 of the Santos Basin.