Introduction

Formation evaluation is the process of: Formation evaluation for petroleum follows some predictable steps. The process for petroleum is aimed at determining, primarily, the water saturation of the target formation zone. Wireline geophysical logs are the lowest cost per unit of information and the most dependable sources of high quality information for formation evaluation. Therefore, the authors will spend most of our effort learning the use of the wireline geophysical logging methods. Thus, they are the primary method by which we determine the formation parameters. The hole may be in poor condition; it may not be straight and it may be filled with a fluid in which we are probably not interested. Therefore, counts per second can be related, quantitatively, to percent uranium, porosity, or other units for which the log was designed.