Relationship between tectonic and paleoenviromental evolution in the Tres Cruces foreland basin, Northwest Argentina.

VILLALBA ULBERICH JUAN P.; GALLI CLAUDIA I.

Vienna

Congreso; European Geosciences Union General Assembly 2018; 2018

European Geosciences Union

The integration of internal features of syntectonic units from the analysis of sedimentary columns, the paleocurrents analysis and the restored basin geometry allow us to link the basin evolution history related to orogenic growth (spatial/temporal loading configuration). In this context, the Tres Cruces basin is located in Northwestern of Argentina on the western margin of the Eastern Cordillera and exhibit a sedimentary fill that would be expected for a foreland basin with an orogenic wedge advancing eastward. Three units can be distinguished: Casa Grande, Rio Grande and Pisungo. Casa Grande has a very difficult contact with Lumbrera Formation. In some places is transitional, in others erosional or by a progressive unconformity. Rio Grande Formation is transitional to Casa Grande in most of the areas and by an unconformity in the East of the basin. The beginning of Pisungo Formation is related with an increment of the size of the clasts and by the presence of Santa Bárbara Subgroup as a member of clasts. The paleo-environment evolves from a meandering system, into a braided system to a proximal alluvial fans composed by debris flows, showing a progradation from a distal to a proximal environment with a progressive decrease of the accommodation space.