Pisco Formation

The Pisco Formation is a geologic formation located in Peru, on the southern coastal desert of Ica and Arequipa. The approximately 640 metres (2,100 ft) thick formation was deposited in the Pisco Basin, spanning an age from the Late Miocene up to the Early Pliocene, roughly from 9.6 to 4.5 Ma. The tuffaceoussandstones, diatomaceoussiltstones, conglomerates and dolomites were deposited in a lagoonal to near-shoreenvironment, in bays similar to other Pacific South American formations as the Bahía Inglesa and Coquimbo Formations of Chile.

The Pisco Formation is considered one of the most important Lagerstätten sites, based on the large amount of exceptionally preserved marine fossils, including sharks (most notably megalodon), birds including penguins, whales and dolphins, marine crocodiles, and Thalassocnus, a marine giant sloths.

Other famous fossils from this site include the giant raptorial sperm whale Livyatan, the sperm whale relative Acrophyseter, and the walrus-like dolphin Odobenocetops.