Controls on deposition of the Tordillo Formation in southern Mendoza (34-36ºS): implications for the Kimmeridgian tectonic setting of the Neuquén basin

JOSÉ FRANCISCO MESCUA; JULIETA SURIANO; LAURA JAZMÍN SCHENCMAN; LAURA BEATRIZ GIAMBIAGI; PATRICIA SRUOGA; ELIZABETH BALGORD; FLORENCIA BECHIS

Opening and Closure of the Neuquén Basin in the Southern Andes

Springer-Verlag

Lugar: Berlin; Año: 2020; p. 127 - 157

The Tordillo Formation is a continental succession of red beds deposited in the Neuquen basin during the Kimmeridgian. Based on sedimentary and structural evidence we document an extensional setting in the northern part of the basin, which contrasts with a transpressional environment in the southernmost section. We disscuss the tectonic setting of the Neuquen basin during the deposition of the Tordillo Formation, which appears controlled by the behavior of the subduction system and the break-up of Pangea. We propose that trench rollback determined a regional extensional setting. This stress field was locally modified by the clockwise rotation of South America due to the initial break-up of Pangea, that ended with the opening of the South Atlantic. This rotation produced a transpressive stress field in the southern Neuquen basin in which the strucures generated during the Permian collission of the Patagonia terrane were reactivated as strike-slip and reverse faults.