EVIDENCIAS DE MIGRACIÓN TERCIARIA DE HIDROCARBUROS EN EL DORSO DE LOS CHIHUIDOS, CUENCA NEUQUINA, ARGENTINA

CEVALLOS, MARTIN; GIUSIANO, ADOLFO; FRANCHINI, MARTA; RAINOLDI, ANA LAURA; MARTINEZ, RICARDO; CARBONE, OSVALDO; ALAIMO, ANDREA

Mendoza

Congreso; IX Congreso de Exploración y Desarrollo de Hidrocarburos; 2014

Instituto Argentino del Petróleo y del Gas

Migration of hydrocarbon to surface is occurring today in many basins, and it is well known to have happen in the Neuquén Basin since its Neogene exhumation. First oil exploitation in the basin involved bitumen veins along the western ranges. Evidences of this process in the basin center gas province are identified in the Dorso de los Chihuidos Arch, a regional anticline structure with 100 km north-south axis. A 100 km long alteration front was mapped in its eastern flank, including mineral alteration and disseminated bitumen. Gas chimneys were identified on seismic in flanks and crest positions. These features appear in the Cuyo Group section and developed upwards until surface levels in correspondence with the mapped alteration front. Neogene inversion formed the Dorso de los Chihuidos Arch and induced failure of its Cretaceous seals. This tectonism occurred after critical moment, when local petroleum systems were mature to overmature, and it triggered migration to surface of vast gas and petroleum volumes. The lost hydrocarbons should be considered in any petroleum system modelling of the region.