Petroleum exploration has always been limited by the lack of adequate subsurface control. Exploration problems are usually problems of extrapolation i.e. to greater depth, to laterally equivalent rocks, or back through time.
Models are widely used as a way of describing complex geological systems so that they can be treated quantitatively and used as the basis for extrapolations and predictions. Models consider, typically, a simplified geological system that can be described mathematically. It is very important to know what simplifying assumptions have been made, when these assumptions are valid, and under what conditions their use may not be appropriate. This requires an understanding of the concepts involved in building the model and how the model operates.
Models are best used as a tool for probing the system and evaluating the sensitivity of the conclusions to possible uncertainties in the values of the input parameters. In a sense, models permit experimental petroleum geochemistry and allow the user to answer the
What if? questions e.g. What if the geothermal gradient had been higher in the past? What if the organic matter type had been different?
This book provides students, exploration geologists, and others who would like to use the available models, with a general idea of how the models work, what they can do, and what their limitations are.
It also provides the information necessary to obtain the input data required by the commercial models.