Control temporal de la apertura de la Cuenca Neuquina a partir de nuevas dataciones U-Pb SHRIMP en circón en el ciclo precuyano del depocentro Cara Cura-Reyes.

Abstract

The Cara Cura-Reyes depocenter started its evolution in the Sinemurian as a half-graben, accommodating voluminous acidic to intermediate volcanic deposits, dated by U-Pb SHRIMP in 198.8 ± 2.0 Ma. Afterwards, the extensional dynamics changed, and the deposits became dominantly sedimentary, in which another SHRIMP U-Pb zircon dating of a tuff gave an age of 195.4 ± 1.0 Ma. This initial volcanism was triggered by the passage of a thermal anomaly beneath Gondwana, generating a typical rift basin. After the effect of this plume dissipated, this depocenter continued accumulating sediments within a back-arc basin, process that continued throughout the rest of the Jurassic and Early Cretaceous times.