Introduction

Abstract

The primary purpose of coring is to obtain rock samples of a sufficient size to obtain estimates of critical reservoir properties. Core analysis provides direct measurements of:

• Porosity — the volume of void space contained in a unit volume of rock

• Permeability — the degree and quality of connection of void spaces which allow fluid flow through the rock

• Saturation — the relative composition of fluid phases filling the void spaces in the rock (the three principle phases are oil, gas and water)

Unlike wireline log and drillstem test analyses which may also give estimates of these properties, core analysis involves making direct measurements upon a known discrete rock sample. Results are therefore more reliable because there are fewer interpretive assumptions.