Seismic Stratigraphy of Cenozoic Deposits in the Salaverry Forearc Basin, Peru: New Insights in Assessing Potential Reservoirs and Plays

Abstract

Abstract This study is focused on the Salaverry Basin, in the forearc of the Peruvian Andes, which contains three oil seeps sampled and analyzed, suggesting at least one active petroleum system within the basin. The development of the basin is controlled by the interaction between the Nazca-Farallon and South American plates, together with Nazca ridge subduction. Seismic stratigraphic analysis calibrated with available well and core data was carried out to understand the spatial-temporal evolution of Cenozoic depositional systems in the basin. As a result, the Cenozoic succession is best subdivided into five second-order sequences (2S1–2S5) composed of nine third-order sequences (3S1–3S9). Subsequently, 3-D seismic geomorphologic analysis afforded images of depositional elements from mapped seismic sequences. Further analysis of these images enhanced interpretation of depositional systems and lithological predictions. Hence, this study adds new potential reservoir rocks into the 2S1, 2S2, 3S2, 3S3, 3S5, and 3S6 sequences and seal rocks into the 3S1, 3S4, 3S5, and 3S7-3S9 sequences, for the petroleum systems previously defined in the basin. These new petroleum system elements are related to the potential plays proposed in this study, which in turn, through a follow-up assessment, could become very attractive exploratory prospects located in the central portion of the Salaverry Basin, shallow water offshore Peru (west South America).