Pisco Formation
Stratigraphic range: Mid Miocene-Early Pleistocene
(Colloncuran-Uquian)
~15–2 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 Middle Miocene up to the Early Pleistocene, roughly from 15 to 2 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,[1][2] 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,[3] the aquatic sloth Thalassocnus,[4] the sperm whale Acrophyseter, and the walrus-like dolphin Odobenocetops.[5]

Description

The Pisco Formation of the Pisco Basin consists of tuffaceous sandstones, diatomaceous yellow to gray siltstones and a basal conglomerate.[6] The formation is deposited from Pisco in the north to Yauca in the south. The northern portion is known as the Ocucaje Area and the southern part as the Sacaco Area.[7] The total thickness of the formation is estimated at 640 metres (2,100 ft).[8] The formation unconformably overlies the Chilcatay and Caballas Formations.

Fauna

The Pisco Formation has provided a rich resource of marine fauna, including marine mammals like cetaceans and seals, large fishes, reptiles, and penguins.[9] It is also one of the richest sites in the world for fossil cetaceans, with close to 500 examples being found in the formation.[10]

The oldest fossils of the aquatic sloth Thalassocnus (T. antiquus) come from the Aguada de Lomas horizon of the Pisco Formation and were dated at roughly 7 Ma. The youngest specimen (T. carolomartini) was found in the Sacaco horizon and dated to approximately 3 Ma.[11] Thalassocnus was preyed upon by the probable apex predators of the environment, Livyatan and megalodon.[12][13] The youngest strata belonging to the formation have been dated at 2 Ma, corresponding to the Early Pleistocene (Uquian). Fossils of the Humboldt penguin were found in these deposits at the Yauca locality.[14]

Vertebrates

Mammal

Pinniped
Pinniped
Taxa Species Description Images Notes
Acrophoca A. longirostirus A large pinniped thought to be the ancestor of the leopard seal
[15]
Australophoca A. changorum TBA
[16]
Hadrokirus H. martini A species of true seal
[15][17]
Hydrarctos H. lomasiensis TBA
[15]
Piscophoca P. pacifica A seal
[18]
Cetacean
Cetacean
Taxa Species Description Images Notes
Acrophyseter A. deinodon A small raptorial physeteroid
[19][20]
A. robustus
Atocetus A. iquensis A small toothed whale
[21][22]
Australithax A. intermedia A long-snouted porpoise
[23]
Balaenoptera B. siberi A baleen cetacean
[16][24]
Belonodelphis B. peruanus An long delphinid
[16][21][25]
Brachydelphis B. jahuayensis An early delphinid
[16][21][26][27]
B. mazeasi
Brujadelphis B. ankylorostris A river delphinid
[28]
Hemisyntrachelus H. oligodon An early form of orca
[15]
Incakujira I. anillodefuego A small baleen cetacean
[16][29]
Kogia K. danomurai A basal member of the Kogia genus. Small physeteroid
[30]
Koristocetus K. pescei A small sperm whale
[31]
Livyatan L. melvillei An 18-meter long raptorial physeteroid with 36 centimetres (1.18 ft) teeth
[3]
Lomacetus L. ginsburgi A cetacean
[16][32]
Miocaperea M. pulchra A cetothere whale
[33]
Ninoziphius N. platyrostris A giant beaked whale
[15]
Odobenocetops O. leptodon A cetacean with dual tusks
[5]
O. peruvianus
Piscobalaena P. nana A small baleen whale
[15][18]
Piscocetus P. sacaco An extinct cetacean
[34]
Piscolithax P. aenigmaticus A porpoise
[15][16]
Pliopontos P. littoralis An early delphinid
[15]
Scaphokogia S. cochlearis An extinct pygmy sperm whale
[16][35]
Xenarthra
Xenarthra
Taxa Species Description Images Notes
Thalassocnus T. antiquus a semi-aquatic marine sloth
[4][15]
[19][34]
T. carolomartini
T. littoralis
T. natans

Fish

Chondrichthyes
Cartilaginous fishes
Taxa Species Description Images Notes
Carcharias C. taurus The sand tiger shark
[15]
Carcharhinus C. sp. indent A requiem shark
[9]
Carcharodon C. carcharias The great white shark
[34][15]
C. hubbelli
Cosmopolitodus C. hastalis The broad-toothed mako
[9]
Hexanchus H. gigas A cow shark
[34]
Isurus I. oxyrhincus The shortfin mako
[16]
Myliobatis M. sp A species of eagle ray
[9]
Otodus O. chubutensis
[9]
O. megalodon The largest of the megatoothed sharks (and of all fishes)
Actinopterygii
Bony fishes
Taxa Species Description Images Notes
Alosinae A. indent A type of herring
[9]
Centropomidae C. aff. Psamoperca A snook fish
[9]
Triglidae T. indent A type of sea robin
[9]
Xiphiidae X. ident A sword fish
[9]
Sardinops S. sp. A sardine
[18]

Birds

Birds
Taxa Species Description Images Notes
Spheniscus S. humbodti Humboldt penguin
[14]
S. megarhampus Banded penguin
[14]
S. muizoni The oldest banded penguin
[36][37]
S. urbinai A larger banded penguin than S. muizoni
[14]
Rhamphastosula R. aguierrei
[15][38]
R. ramirezi
Sula S. brandi
[19][39]
S. magna
S. sulita
Morus M. peruvianus
[19]
Perugyps P. diazi
[19]
Fulmarus Fulmarus sp.
[15]
Pelagornis Pelagornis sp.
[16][40]
Pelecanus Pelecanus sp.
[41]
Phalacrocorax P. aff. bougainvillii
[15][42]
cf. Phalacrocorax sp.

Reptiles

Reptiles
Taxa Species Description Images Notes
Sacacosuchus S. cordovai A gavialid crocodylian
[43]
Piscogavialis P. jugaliperforatus A gryposuchine gavialid crocodylian
[19][18]
Pacifichelys P. urbinai A sea turtle
[12][44]
Chelonia Cheloniidae indet.
[9]
Eusuchia E. sp.
[15]

Invertebrates

Invertebrates
Fossils Notes
Acanthina obesa, A. triangularis, Concholepas kieneri, Anadara sp., Dosinia sp., Herminespina sp.
[15]

Correlations

Laventan

Laventan correlations in South America
Formation Honda Honda Aisol Cura-Mallín Pisco Ipururo Pebas Capadare Urumaco Inés Paraná Map
Basin VSM Honda San Rafael Caldera Pisco Ucayali Amazon Falcón Venezuela Paraná
Pisco Formation is located in South America
Pisco Formation
Pisco Formation
Pisco Formation
Pisco Formation
Pisco Formation
Pisco Formation
Pisco Formation
Pisco Formation
Pisco Formation
Pisco Formation
Pisco Formation
Pisco Formation (South America)
Country  Colombia  Bolivia  Argentina  Chile  Peru  Venezuela  Argentina
Boreostemma
Hapalops
Miocochilius
Theosodon
Xenastrapotherium
Mylodontidae
Sparassodonta
Primates
Rodents
Birds
Terror birds
Reptiles
megalodon
Flora
Insects
Environments Fluvial Fluvio-deltaic Fluvio-lacustrine Fluvio-deltaic Fluvial
Laventan volcanoclastics

Laventan fauna

Laventan flora
Volcanic Yes

See also

References

  1. ^ Brand et al., 2004
  2. ^ Brand et al., 2011
  3. ^ a b Lambert et al., 2010
  4. ^ a b De Muizon et al., 2003
  5. ^ a b De Muizon & Domning, 2002
  6. ^ Báez Gómez, 2006, p.65
  7. ^ Stucchi, 2007, p.368
  8. ^ Altamirano Sierra, 2013, p.3
  9. ^ a b c d e f g h i j Báez Gómez, 2006, p.66
  10. ^ Poma Porras et al., 2009, p.86
  11. ^ De Muizon et al., 2004, p.287
  12. ^ a b Parham & Pyenson, 2010, p.231
  13. ^ Bianucci et al., 2015, p.543
  14. ^ a b c d Stucchi, 2007, p.370
  15. ^ a b c d e f g h i j k l m n o p Sud Sacaco West at Fossilworks.org
  16. ^ a b c d e f g h i j Aguada de Loma at Fossilworks.org
  17. ^ Amson & De Muizon, 2014, p.524
  18. ^ a b c d Hueso Blanco at Fossilworks.org
  19. ^ a b c d e f Sud Sacaco at Fossilworks.org
  20. ^ Lambert et al., 2008
  21. ^ a b c Cerro la Bruja at Fossilworks.org
  22. ^ De Muizon, 1988, p.131
  23. ^ De Muizon, 1988, p.88
  24. ^ Demeré et al., 2005, p.115
  25. ^ De Muizon, 1988, p.192
  26. ^ De Muizon, 1988, p.82
  27. ^ De Muizon, 1988, p.108
  28. ^ Lambert et al., 2017
  29. ^ Marx & Kohno, 2016, p.5
  30. ^ Benites‐Palomino, Aldo; Vélez‐Juarbe, Jorge; Collareta, Alberto; Ochoa, Diana; Altamirano, Ali; Carré, Matthieu; Laime, Manuel J.; Urbina, Mario; Salas‐Gismondi, Rodolfo (August 2021). Lautenschlager, Stephan (ed.). "Nasal compartmentalization in Kogiidae (Cetacea, Physeteroidea): insights from a new late Miocene dwarf sperm whale from the Pisco Formation". Papers in Palaeontology. 7 (3): 1507–1524. doi:10.1002/spp2.1351. ISSN 2056-2799. S2CID 234058681.
  31. ^ Collareta et al., 2017, p.261
  32. ^ De Muizon, 1988, p.27
  33. ^ Miocaperea pulchra at Fossilworks.org
  34. ^ a b c d Sacaco at Fossilworks.org
  35. ^ De Muizon, 1988, p.66
  36. ^ Göhlich, 2007, p.287
  37. ^ Stucchi, 2007, p.369
  38. ^ Stucchi et al., 2016, p.423
  39. ^ Stucchi et al., 2016, p.419
  40. ^ Chávez et al., 2007
  41. ^ Altamirano Sierra, 2013, p.6
  42. ^ Yauca at Fossilworks.org
  43. ^ Salas-Gismondi, R.; Ochoa, D.; Jouve, S.; Romero, P.E.; Cardich, J.; Perez, A.; DeVries, T.; Baby, P.; Urbina, M.; Carré, M. (2022-05-11). "Miocene fossils from the southeastern Pacific shed light on the last radiation of marine crocodylians". Proceedings of the Royal Society B. 289 (1974). doi:10.1098/rspb.2022.0380. PMC 9091840. PMID 35538785.
  44. ^ Cerro Colorado Pisco at Fossilworks.org

Bibliography

Further reading

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