Chapter 33 - Structural development in the frontal Malargüe fold and thrust belt, Neuquén Basin, Argentina

Abstract

The study of deformation fronts located at the foothills of the Andes was for many years one of the objectives for oil and gas exploration in the Neuquén Basin. In the last decades some of these oil fields reach the status of mature oil fields related to structural oil traps. This chapter shows the interpretation of the frontal Malargüe Fold and Thrust Belt. The methodology applied involves 3D-PDSM seismic data and TecVa processing, integrated with surface and well data. The frontal Malargüe fold and thrust belt shows two opposite verging main structures, the El Sosneado thrust to the west, and the La Paloma fault to the east. At depth, these structural features were developed, due to the shortening transferred by El Sosneado thrust to the east. A common detachment level at the base of Agrio Formation generates anticlines in mesozoic sequences that are controlling the position of the oil fields in the fold and thrust belt. Synorogenic deposits were recognized at the central zone, showing a Miocene activity. In addition, a surface analog was studied where equivalent structures were recognized and compared with those observed in the subsurface.