2.1 Introduction

The oil and gas industry is a technology-driven industry. Our ability to locate and extract hydrocarbons from beneath the ground's surface is tied directly to the evolution of technologies, concepts, and interpretative sciences. Figure 2.1 illustrates how petroleum-recovery efficiency has improved since 1950. Interpretation techniques and concepts are listed by year beneath the black curve, and related new technologies are listed above the curve. The technologies are mainly seismic-based methods for imaging features beneath the ground's surface. Other technologies that also have vastly improved our ability to extract hydrocarbons include advances in well logging techniques, improvements in our ability to drill in deep water beyond the continental shelf, and the advent of horizontal drilling, to name a few.

Figure 2.1: Graph showing the US discovery and recovery efficiencies since 1950. Blue ^[1]/black line is a normalized curve. Also plotted are the timing of major technology developments (green/dark arrows) and new interpretive disciplines (yellow/bright arrows). Figure is modified significantly from Fisher (1991). (Reprinted with permission of The Leading Edge.)

This chapter provides an overview of the common techniques for characterizing oil and gas reservoirs. The techniques can be subdivided into those that measure static reservoir properties and those that measure dynamic reservoir properties.