Bed 25, Section 3 - Hualgayoc [Yumagual Fm] (Cretaceous of Peru)

Where: Peru (6.8° S, 78.6° W: paleocoordinates 13.6° S, 52.5° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Yumagual Formation, Late/Upper Albian (105.3 - 99.6 Ma)

• LITHOSTRATIGRAPHY: From the Yumagual Fm, which is locally overlain by the Mujarrún Fm (Cenomanian), and overlies the Pariatambo Fm (Middle Albian). AGE: Late Albian-Early Cenomanian, on the basis of ammonite biostratigraphy; Ostrea scypax zone; placed here in Late Albian on the basis of stratigraphic position. STRATIGRAPHIC POSITION: Collection from 189 m thick marl unit, near the middle of the section.

• bed-level stratigraphic resolution

Environment/lithology: coastal; poorly lithified, gray marl and lithified, gray limestone

• LITHOLOGY: Marl, light gray, soft, poorly exposed, with interbeds of massive, medium- to thick-bedded fossiliferous, medium gray, bituminous limestone. LITHIFICATION: Poorly lithified, on the basis of facies description.

Size class: macrofossils

Collected by Benavides; reposited in the AMNH

Collection methods: surface (in situ),

• COLLECTOR: V. E. Benavides. REPOSITORY: 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 88142: authorized by Austin Hendy, entered by Austin Hendy on 01.04.2009

Creative Commons license: CC BY (attribution)

Taxonomic list

• COVERAGE: Probably not exhaustive, but representative for ammonoids, bivalves, and other invertebrates groups. NOMENCLATURE: Authoritative publication, but with somewhat antiquated nomenclature, and species-resolution identifications.
Show authors, comments, and common names
Bivalvia
 Ostreida - Ostreidae
Ostrea sp.
Ostrea sp. Linnaeus 1758 oyster
 Ostreida - Gryphaeidae
Exogyra sp.
Exogyra sp. Say 1820 oyster