Chapter 11 - Mathematical Modeling of Geological Processes (Dynamic Geological Systems)

Abstract

The chapter, using numerical simulation, shows that modeling coefficients adequately represent the influence of many geological factors on the petrophysical properties of rocks that in turn signifies that the reservoir properties of Mesozoic and Neogene rocks are very different. The chapter also highlights that geological time is the main factor determining the degree of rock compaction. By comparing the results obtained by the simulation of clastic reservoir rock properties, such as sandstones, with those of carbonate rocks, the chapter explains that the carbonate rocks become compacted and consolidate faster than the sandstones. The results of the numerical simulation also indicated that statistical distributions of porosity and density obey the normal law, whereas the distribution of permeability obeys the lognormal law. The chapter presents a multivariable model of lithification of both terrigenous and carbonates sediments in rocks. This model is an integral part of the models used for predicting the properties, such as porosity, permeability, and bulk density, of oil and gas bearing rocks. The relationships between absolute and normalized values of geologic factors are established on the basis of these experimental and field data, using which the chapter proposes models for the evaluation of both reservoir rock and caprock properties. The chapter also presents software for the calculation of rock properties, and then calculates the reservoir rock and caprock properties at reservoir temperature and pressure using both the computer program and the proposed models. The chapter also verifies the proposed method of numerical simulation of oil and gas bearing rock properties using numerous examples.