Jama Formation

The Jama Formation is a Pliocene to Early Pleistocene (Montehermosan to Ensenadan in the SALMA classification) geologic formation in Ecuador. The claystones and sandstones were deposited in an coastal environment. The age of the Jama Formation is constrained by 40Ar/39Ar dating of tephra beds. The formation is correlated to the Charco Azul Formation of western Panama and southeastern Costa Rica.
Subdivision.
The formation is subdivided in, from top to base:
Fossil content.
The formation has provided bivalve, gastropod and scaphopod fossils.