Estimating Permeability in a Carbonate Reservoir of Campos Basin Combining Well Logs and Multiple Linear Regressions

Abstract

From the data set of two wells drilled in a carbonate reservoir in Campos Basin - Southeastern Brazil, this article made the estimation of permeability using geophysical well logs in conjunction with the multiple linear regression technique. The main difficulty to characterize this type of reservoirs consists in that the carbonates have a broad variance in their physical attributes. For this understanding, it was then projected to separate the reservoir into zones according to their different petrophysical features. So, based on gamma rays, resistivity, density, neutronic and sonic logs, certain parameters of the reservoir such as irreducible water saturation, top and bottom of the reservoir, oil/water contact, porosity and oil-producing areas were determined. In addition, geological attributes were applied to validate qualitatively the study, when the reservoir was divided into zones in conformity with the environment energy at the time of deposition of the deposits. In the final, the estimate showed good fit with the permeability measurements in the laboratory through of this simple and fast method.