Papo Seco Formation

The Papo Seco Formation is a geological formation in Portugal, whose strata date back to the Early Cretaceous. Dinosaur fossils are among the fossils that have been recovered from the formation.

Name
The unit was previously referred to as the "Gres a Dinosauriens", due to the abundant dinosaur remains found in the past.

Description
The Papo Seco Formation (Rey, 1992) marks the return to clastic-dominated sedimentation. Exposure of the formation is found above the low cliff between Rochadouro and Areia do Mastro, and on the foreshore and beach at Boca do Chapim. The Papo Seco Formation is dominated by silty mud-mud deposition. This is interbedded with medium to coarse, commonly ribbon shaped, clastic sandstones. Along the exposure, between Rochadouro and Boca do Chapim, the clastic sands are not laterally continuous. The exposure clearly shows that the ribbon sands are isolated and change laterally into muds. Three distinct sand facies have been identified within the Papo Seco Formation.