Evidence purported to document the influence of various controls on diagenetic processes or on reservoir properties abounds in the literature. However, such evidence often consists of simple crossplots in which the influences of only one or, at most, two variables are displayed. In most cases, the influences of other variables to which the same effects might be attributed are not discussed, or they are claimed to have a minimal effect or be held constant. Seldom is the data backing up these claims presented or available to outside workers. As a result, the reader is forced to accept these claims on faith alone, or to base his acceptance on prior knowledge of the unit, area, or relationship being discussed.

It is not the intent here to present incontrovertible evidence regarding the relative importance of each of the factors which control the major diagenetic processes. The data to accomplish that are simply not available. As discussed in Chapter 5, many of the controlling processes are still in question, and even where general agreement exists with respect to the importance of a particular process, the factors that control that process are commonly not fully understood. This chapter will, therefore, review examples of evidence presented in the literature which are claimed to support the importance of a particular control. This will give the reader an overview of those variables which are considered by specialists to play a major role in controlling diagenesis. Some of these factors may indeed be very important, while others may