Evaluating the Correlation Between Petrophysical and Geomechanical Properties of Samples from the Defa Field

Abstract

The two characteristics of rock are its mechanical and physical attributes. Through non-destructive testing, the physical characteristics of rocks are determined. Density, specific gravity, water content, saturation level, porosity, and pore number are the physical characteristics of rocks. On the other hand, destructive testing is used to determine mechanical properties. Compressive and tensile strength tests are examples of mechanical qualities that are acquired through laboratory testing.

In many geological issues, porosity and density are essential and significant physical characteristics of rocks that influence other physical characteristics. Consequently, measurements of the density and porosity of rock samples are crucial research topics in the fields of geoscience and geoengineering. There are numerous methods for measuring density and porosity that are currently in use. Because different measurement techniques are based on different concepts and test procedures, it is required to compare the measurement results from these approaches in order to ensure the quality of the data and to assess its quality. As study materials, we gathered eight different kinds of rock samples from Waha Oil Company's Defa Field. We also prepared a number of metal specimens for experimental comparison.

The eight rocks had porosities that ranged widely, from roughly 0.3% to 50%. We measured the volumes of regularly shaped specimens and calculated their bulk densities and porosities using three different techniques: a helium-displacement pycnometer, a buoyancy test, and a calliper. As a result, the three techniques yielded almost same bulk densities and porosities for all the specimens.

Furthermore, we used mercury intrusion porosimetry to quantify the rock samples' density and porosity and ascertain their pore size distribution. Porosity values obtained by the porosimetry method were underestimated in the case of high-porosity (soft) rock samples and overestimated for the very low-porosity rock samples. Ability to determine pore size distribution, however, is a very important advantage of the porosimetry method.