We analized body-waves of local and regional earthquakes recorded on the Seismic Network of Northeastern Sonora, México (RESNES) are used to determine empirical attenuation functions for P and S waves in the interval of 0.4-63 Hz. The epicenters are near…

Crinoid columnals and pluricolumnals assigned to five species, Pentaridica (col.) rothi Moore and Jeffords, Cyclocaudex cf. C. (col.) jucundus Moore and Jeffords, Cyclocaudex cf. C. (col.) costatus Moore and Jeffords, Preptopremnum (col.) rugosum Moore and Jeffords, and Heterostelechus (col.) texanus…

The fossil-rich deposits of Térapa (east-central Sonora) contain more than 60 zoological taxa, many with tropical affinities such as Crocodylus (crocodylian), Hydrochaeris (capybara), and many birds. The deposits also contain the dermal ossicles (osteoderms) of two extinct xenarthrans, a glyptodont…

The present contribution is the first instalment in a systematic revision of the corals from the Sonoran Bisbee Group (late Barremian to early Albian). The article gives a short overview on the lithostratigraphy and outcrops of the study area and…

Jaguars are endangered in Mexico and the United States, necessitating careful monitoring of population status. We determined minimum numbers of jaguars and sympatric pumas in a small population in northern Sonora, Mexico, the nearest known breeding population to the United…

The Late Cretaceous-early Tertiary (Laramide) orogeny (90-40 Ma) in the northwestern part of Mexico produced an important calc-alkaline magmatism, accompanied by several associated porphyry copper and skarn deposits. In the Sierra Santo Niño, Sonora, the Bacanora batholith intrusive complex, composed…

Beach sand samples collected from two localities of the Gulf of California (Puerto Peñasco and Bahia Kino, Sonora) were analyzed in order to identify their provenance and depositional history on the basis of the different microtextures on the quartz grains.…

A roundness analysis of quartz grains (n=54) from dunes from San Luis Río Colorado (SLRC), El Pinacate (EP), Golfo de Santa Clara (GSC) and Puerto Peñasco (PP), Sonora, Mexico, was carried out in order to determine the provenance of quartz…

Detrital zircon U-Pb geochronology from each of the formations of the Triassic-Lower Jurassic Barranca and El Antimonio groups of central and northwestern Sonora and from the Lower Jurassic Basomari and Middle Jurassic Lily formations of northern Sonora indicate they contain…

The Arizpe sub-basin located in the northern part of the Río Sonora basin is a Basin and Range half-graben that initiated during Late Oligocene time in north-central Sonora. Its ~2.1 km-thick, east-dipping volcanic and sedimentary fill assigned to the Báucarit…