SEISMOLOGICAL STUDY AT THE HIGHEST OIL EXPLOTATION REGION IN ARGENTINA

CORREA, SEBASTIAN; NACIF, ANDRES; NACIF, SILVINA; FURLANI, RENZO; GIMENEZ, MARIO E

Santiago

Simposio; Primer Simposio de Tectónica Sudamericana; 2016

Asociacion Sudamericana de Tectónica

A seismological network was established by installing 11 broad band stations covering an area of ~ 70 km x 70 km on the Northern-Central Neuquén basin region and it recorded continuous data from November 2014 to July 2016. There is no other seismological network in the region for which the low magnitude seismicity is not known. The closer seismological study to the area was presented by Bohm et al. 2002, and it covers mainly the southern central region of Chile. The triangular Neuquén Basin is located in the Andean foreland of western Argentina, between 36°S and 40°S. It appeared as a back‐arc basin east of the Andean volcanic arc. The evolution and development of the Neuquén basin was controlled by tectonic changes on the western margin of Gondwana (Howell et al. 2005). The Vaca Muerta formation is one of the four charging systems linked to source rocks from the Early Jurassic until the Early Cretaceous within the Neuquén basin. The seismological experiment hereby presented has as main objective to determine the base seismicity in the Añelo region (main scenario for the non-conventional oil extraction techniques) to be able to identify possible neo-tectonic activity and also associated seismicity to the injection of fluids. The routine data processing was performed using the SEISAN Seismological Platform. A visual inspection was carried to find seismic events using the Multitrace module. An event data base was created after continuous registers were observed; in this manner the number of seismic events which were found was maximized. Multitrace View was used for P and S waves arrival identification and coda magnitude was determined in vertical channel. Several events were detected and its location was determined along with their magnitude. Location parameters were found using Hypocenter software and one-dimensional velocity model from VSP data and Bohm et al. 2002 one-dimensional velocity model. The data processing of barely 3 months delivered firstly, 2 groups of very low magnitude (Mc