Integration of 3D Seismic and Production Data in Secondary Recovery Analysis, Puesto Hernandez Field, Neuquén, Argentina

Abstract

Abstract The object of this work was to optimize a waterflood project in a highly complex structural-stratigraphic area. A geophysicist, two waterflood-monitoring engineers and a numerical simulation specialist made up the multidisciplinary team created for the project. The goal was to explain the low response to water injection in the subject area, i.e. the injection well behavior (variation in the admitted volume, overpressurization, etc.), and the corresponding shortage in production wells. The information used for this study consisted in 3D seismic data, interpreted well logs, correlation, transient pressure tests, production and injection history, hydraulic connectivity analysis and previous structural interpretations. A radioactive tracer test was also conducted. Seismic cross-section were developed between wells in order to detect structural and stratigraphic lineaments. Then, a seismic attribute analysis was performed. The reflection strength and the amplitude attribute reflected clearly the thickness loss northward and the deterioration of the petrophysical properties toward the east. The instantaneous phase attribute was used to interpret the structural frame but no significant results were obtained. A reliable correlation between petrophysical information and seismic data was achieved. After defining the structural – stratigraphic frame, the information above was related to the production and injection history of the area. Some old build up and fall off tests were reviewed in order to confirm the existence of faults and petrophysical changes. Based on this analysis, some proposals were drawn to improve 1the production and injection behavior of the pattern, namely, horizontal drilling from existing vertical wells, acid treatment, hydraulic fracturing and the drilling of a horizontal well in an unswept area. The reservoir water saturation distribution was evaluated for each proposal using a numerical simulation model and a cost-effective analysis of the proposals was carried out.