Paleontología y geoquímica de la Formación Agua de la Zorra, Triásico Medio a Superior de la Cuenca Cuyana, provincia de Mendoza

Abstract

The Agua de la Zorra Formation deposits represent a deltaic-lacustrine system. The unit includes Corystospermales, together with Equisetales that would correspond to a delta deposit with scarce kerogen; the palynoflora includes complete to fragmented leaves and stems. The upper part would represent prodeltas to offshore lacustrine deposits, bearing variable amounts of non-fluorescent amorphous kerogen; the megaflora remains are relatively small size, partially broken and degraded. The stacking pattern shows a progressive deepening of the lacustrine system that correlates with an increase upwards of the abundance of organic matter (OM) preserved. The increase of the K/Rb ratio to the top of the sequence suggests a terrigenous origin of the kerogen in the deepest horizons of the lake. The analysis of the Cr/Zr ratio, together with the presence of V would indicate the existence of basic rocks in the provenance area of the basin.