ammonites
Bed 26, Section 1 - Lajas (Yumagual Fm) (Cretaceous of Peru)

Where: Cajamarca, Peru (6.6° S, 78.7° W: paleocoordinates 13.3° S, 54.2° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Yumagual Formation (Pulluicana Group), Cenomanian (99.6 - 93.5 Ma)

• Collection from a 4 m thick shale unit, lying below the Choro Member of the Mujarrun Formation (early Cenomanian) and above the Pariatambo Formation (middle Albian). The member is as much as 760 m thick in the region. The formation contains two biozones, a lower zone with late Albian index taxa, and an upper zone with early Cenomanian fauna.

• bed-level stratigraphic resolution

Environment/lithology: marine; lithified, shelly/skeletal, calcareous shale

• Accumulated during a shallowing of regional seas, with accumulation of shallow-water marls and limesyones, with occasional interfingering quartz-siltstones, with abundant benthic life, but scarce ammonites.
• Shale, calcareous, 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 56907: authorized by Austin Hendy, entered by Austin Hendy on 28.11.2005

Creative Commons license: CC BY-NC-ND (attribution-noncommercial-no derivatives)