Bed 50, Section 5 - Cajamarca (Inca Fm) (Cretaceous of Peru)

Where: Cajamarca, Peru (7.2° S, 78.5° W: paleocoordinates 12.7° S, 50.5° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Inca Formation, Albian (113.0 - 100.5 Ma)

• Collection from a 2 m thick limestone unit, lying below the Chulec Formation (early middle Albian) and not far above the Goyllarisquisga Formation, seperated by a disconformiy. The Inca Formation is 80 m thick at this section. The formation was believed to be Aptian by Steinmann (1930), although the present writer believes the unit to be early Albian on the basis of faunal affinities (Parahoplites biozone) and bounding chronostratigraphic relationships.

• bed-level stratigraphic resolution

Environment/lithology: coastal; lithified, concretionary, shelly/skeletal, gray limestone

• The Inca Formation was deposited under shallow marine conditions. The abundance and diversity of species, the presence of Lingula and of crabs indicate a nearshore environment.
• Limestone, gray, slightly nodular, fossiliferous.

Size class: macrofossils

Reposited in the AMNH

Collection methods: quarrying,

• Collections reposited at AMNH.

Primary reference: V.E. Benavides-Caceres. 1956. Cretaceous system in northern Peru. Bulletin of the American Museum of Natural History 108(4):1-493 [A. Miller/A. Hendy]more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 56946: authorized by Austin Hendy, entered by Austin Hendy on 29.11.2005

Creative Commons license: CC BY (attribution)

Taxonomic list

• Taxonomic list compiled by the author during 1951-1952. Nomenclature should therefore be somewhat antiquated, though systematics reflect supervision of Normal Newell, Columbia University and AMNH paleontologists.
unclassified
  -
Cephalopoda
 Ammonitida - Acanthohoplitidae
Parahoplites quilla Benavides-Caceres 1956 ammonite
Bivalvia
 Trigoniida - Trigoniidae
Buchotrigonia abrupta von Buch 1838 clam
 Trigoniida - Megatrigonioidae
 Trigoniida - Steinmanellidae