Modelado de Inversión Gravimétrica en la Faja Plegada y Corrida, Cuenca Neuquina

MARTINEZ, M PATRICIA; LINCE KLINGER, FEDERICO; FRISCHBUTTER, A; VILA MARIO; GIMENEZ, MARIO E; RUÍZ, FANCISCO

Mar del Plata

Congreso; 6º Congreso de Exploración y Desarrollo de Hidrocarburos; 2005

Abstract: A 2D gravimetric inversion model applied to a survey conducted in the Ranquil Norte Area south of the Mendoza Province is presented. The study area is characterized by a well exposed and, an intensively folded and faulted Cretaceous sedimentary column The Free Air reduction as well as Topographic and Bouger corrections have been applied to the gravity field measurements. The gravimetric effect of the Moho for a transcontinental section parallel to 36º S was used as a regional anomaly. Based on the structural surface analysis (dip measurements), geological mapping and considering the regional geological framework of the Neuquen Basin fold and thrust belt , two east-west cross section were modeled. applying a basement involved tectonic inversion model with different lateral displacement. Based on these structural cross sections two gravimetric models, using the densities of the different lithological units involved, have been calculated. The formation density values were obtained from borehole e-logs of nearby wells. The densities, thicknesses and depths of the geological units were adjusted in an iterative process with the objective of matching the calculated gravity model with the field measures. The tectonic inversion model (minimum lateral displacement), with significant basement uplift, reached the best fit with the field data. The thickness variation of the evaporites of the Huitrin Formation along the sections is the main modeling factor of the gravimetric model.