Comparing laboratory and well log petrophysical properties in an albian carbonate reservoir of southeastern Brazil

Abstract

This study evaluated the petrophysical properties of an Albian carbonate reservoir, positioned in the post-salt layer, located in the Campos Basin, Southeastern Brazil. Geological information, geophysical well logs, and, laboratory experimental data with samples were used to do this. Based on density, neutron and sonic logs, different approaches were used to determine the porosity. The Nuclear Magnetic Resonance log was also used to evaluate both porosity and permeability, this last with various methods. In the sequence, all these estimates were compared between them and the laboratory experimental data. The results show that, an estimation of the porosity is much easier than an evaluation of the permeability. This is demonstrated when the porosity is determined, with a good fit, in a multiple linear regression, whereas, the permeability is only evaluated, with good fit, in a multiple polynomial regression.