Ichnology and sedimentology of the Upper Jurassic - Lower Cretaceous Vaca Muerta Formation, central Neuquen basin

PAZ, M.; DESJARDINS, P.,; MÁNGANO, M. GABRIELA; BUATOIS, L.A.; PONCE, J.J.; CARMONA, N.B.; FANTÍN, M.A.; REIJENSTEIN, H.; VALLEJO, M.D.

Tucumán

Congreso; XX Congreso Geológico Argentino; 2017

Asociación Geológica Argentina

An integrated sedimentological and ichnological analysis of the Vaca Muerta Formation, based on cores from the central zone of the Neuquén basin, indicates that this unit is represented by outer ramp and basin facies associations, showing six trace-fossil assemblages. Oxygenation and substrate consistency were two significant limiting factors for development of the benthic fauna. Outer ramp and basin facies were deposited under oxygen-deficient conditions, punctuated by short-term oxygenated events which were more persistent in the outer ramp. The outer ramp facies shows a less abundance of soupgrounds compared with the basin facies, due to higher erosion and deposition of sediment with higher carbonate content,under more energetic conditions.