Permian-triassic boundary at El Antimonio, Sonora, Mexico


Por: Lucas S.G., Kues B.S., Estep J.W., González-León C.M.

Publicada: 1 ene 1997
Resumen:
Newly discovered fossils indicate the Permian-Triassic boundary is in the lower Antimonio Formation. A brachiopod-dominated assemblage collected 40 m above the Monos-Antimonio Formations contact indicates a middle Permian (Guadalupian) age, and ammonites and conodonts found 380 to 530 m above the base of the Antimonio Formation indicate an Early Triassic (Spathian) age. The lower Antimonio Formation contains three unconformity-bounded sequences, one of middle Permian age, a second one of Permian or Early Triassic age and the other of Spathian age. It thus resembles Lower Triassic strata in the southwestern United States (especially southern Nevada and adjoining areas), in recording only two of the three known Early Triassic eustatic cycles.

Filiaciones:
Lucas S.G.:
 New Mexico Museum of Natural History and Science, 1801 Mountain Road N.W., Albuquerque, NM 87104-1375, United States

Kues B.S.:
 Department of Earth and Planetary Sciences, University of New Mexico, Albuquerque, NM 87131, United States

Estep J.W.:
 New Mexico Museum of Natural History and Science, 1801 Mountain Road N.W., Albuquerque, NM 87104-1375, United States

González-León C.M.:
 Estación Regional del Noroeste, Instituto de Geología, Universidad Nacional Autónoma de México, Apartado Postal 1039, 83000 Hermosillo, Sonora, Mexico
ISSN: 10268774
Editorial
CENTRO GEOCIENCIAS UNAM, CENTRO GEOCIENCIAS, UNAM, CAMPUS JURIQUILLA, QUERETARO, QRO 76230, MEXICO, México
Tipo de documento: Article
Volumen: 14 Número: 2
Páginas: 149-154

MÉTRICAS