Pisco Formation

Pisco Formation
Stratigraphic range: Late Miocene-Early Pliocene
(Tortonian-Zanclean)[1]
~9.6–4.5 Ma
Lithology and sediments of the Pisco Formation across its allomembers
TypeGeological formation
Unit ofPisco Basin
OverliesChilcatay & Caballas Formations
Thickness640 m (2,100 ft)
Lithology
PrimaryTuffaceous sandstone, diatomaceous siltstone
OtherConglomerate, dolomite
Location
Coordinates15°42′S 74°30′W / 15.7°S 74.5°W / -15.7; -74.5
Approximate paleocoordinates15°48′S 73°48′W / 15.8°S 73.8°W / -15.8; -73.8
RegionArequipa & Ica Regions
Country Peru
ExtentFrom Pisco to Yauca
Type section
Named forPisco
Pisco Formation is located in Peru
Pisco Formation
Pisco Formation
Pisco Formation
Pisco Formation
Pisco Formation
Pisco Formation
Pisco Formation
Pisco Formation
Pisco Formation
Pisco Formation
Pisco Formation
Pisco Formation
Pisco Formation
Pisco Formation
Outcrops of the formation in Peru

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 tuffaceous sandstones, diatomaceous siltstones, conglomerates and dolomites were deposited in a lagoonal to near-shore environment, in bays similar to other Pacific South American formations as the Bahía Inglesa and Coquimbo Formations of Chile.

Several specialists consider the Pisco Formation one of the most important Lagerstätten,[2][3] based on the large amount of exceptionally preserved marine fossils, including sharks (most notably megalodon), penguins, whales, dolphins, birds, marine crocodiles and aquatic giant sloths.

Famous fossils found in these layers include the giant raptorial sperm whale Livyatan,[4] the aquatic sloth Thalassocnus,[5] the sperm whale Acrophyseter, and the walrus-like dolphin Odobenocetops.[6]

  1. ^ Ochoa, Diana; DeVries, Thomas J.; Quispe, Kelly; Barbosa-Espitia, Angel; Salas-Gismondi, Rodolfo; Foster, David A.; Gonzales, Renzo; Revillon, Sidoine; Berrospi, Raul; Pairazamán, Luis; Cardich, Jorge; Perez, Alexander; Romero, Pedro; Urbina, Mario; Carré, Matthieu (2022). "Age and provenance of the Mio-Pleistocene sediments from the Sacaco area, Peruvian continental margin". Journal of South American Earth Sciences. 116: 103799. doi:10.1016/j.jsames.2022.103799. ISSN 0895-9811.
  2. ^ Brand et al., 2004
  3. ^ Brand et al., 2011
  4. ^ Lambert et al., 2010
  5. ^ De Muizon et al., 2003
  6. ^ De Muizon & Domning, 2002