Section of Sierra del Alamo, L11 (Jurassic of Mexico)

Where: Sonora, Mexico (30.6° N, 112.6° W: paleocoordinates 15.8° N, 55.7° W)

• coordinate estimated from map

• local area-level geographic resolution

When: Rursicostatum ammonoid zone, Lower Jurassic upper Member (Sierra de Santa Rosa Formation), Late/Upper Hettangian (201.3 - 196.5 Ma)

• Sequence X, informal unit 16

Environment/lithology: deep-water; lithified siliciclastic sediments

• Siliciclastic strata, in its higher part interbedded with calcareous mudstone and bioclastic limestone beds.

Size class: macrofossils

Preservation: cast, mold/impression

Collection methods: surface (in situ)

• Estación Regional del Noroeste (ERNO), Instituto de Geología,Universidad Nacional Autónoma de México collection

Primary reference: D. Szűcs, C. M. González-León, and J. Pálfy. 2019. Ammonoid biostratigraphy and paleobiogeography of Lower Jurassic sections from Sonora (northwest Mexico) and their tectonic implications. Journal of South American Earth Sciences 93:267-282 [J. Pálfy/D. Juhász/P. Wagner]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 208237: authorized by József Pálfy, entered by Dorina Juhász on 25.03.2020

Creative Commons license: CC BY (attribution)

Taxonomic list

Show authors, comments, and common names
Cephalopoda
 Ammonitida - Psiloceratidae
Badouxia cf. mexicana, Badouxia sp., Badouxia cf. castlensis
Badouxia sp. Guex and Taylor 1976 ammonite
Badouxia cf. castlensis Longridge et al. 2006 ammonite