Analysis of Mechanical Behaviour of Reservoir Rock Properties

Abstract

In petroleum industry, rock mechanical behaviour is a fundamental parameter for the development of oil and gas fields. Overburden stress must be accredited when determining the mechanical properties of rocks as it contributed to part of the rock strength. This paper is to study the influence of petrophysical properties, grain size, cement types, microfractures, mineral composition and mineral structure on the rock mechanical properties. Porosity and permeability of five sandstone cores were measured using Ultra-Pore™ 300 and CMS™-300 Automated Parameter. Petrographic analyses of thin sections were performed to determine the mineral composition, while the mineral structure was observed by using Dino-Lite microscope. The cores were tested for present of carbonate minerals using hydrochloric acid. Finally, the rock mechanical behaviour were analyzed by relating all the factors mentioned with the fracture density of the rock. The result showed that the porosity, grain size, cement types, mineral composition and structure are closely related to the mechanical behaviour of rock. With the decrease in grain size and quartz grain along with depth, the porosity and fracture density of sandstones decrease, and thus having a greater rock strength. In addition, the sandstones with the present of clay matrix and carbonate cement have a lower mechanical strength as compared to the sandstones with clay matrix and quartz cement.