Sedimentary rocks form at low temperatures and pressures at the surface of Earth owing to deposition by water, wind, or ice. By contrast, igneous and metamorphic rocks form mainly below Earth’s surface where temperatures and pressures may be orders of magnitude higher than those at the surface, although volcanic rocks eventually cool at the surface. These fundamental differences in the origin of rocks lead to differences in physical and chemical characteristics that distinguish one kind of rock from another. Sedimentary rocks are characterized particularly by the presence of layers, although layers are also present in some volcanic and metamorphic rocks, and by distinctive textures and structures. Many sedimentary rocks are also distinguished from igneous and metamorphic rocks by their mineral and chemical compositions and fossil content.

It is always easier to write a textbook the second time around, or so I thought. Writing my first textbook entitled “Earth’s Materials: Minerals and Rocks” (published in 2001 by Prentice-Hall) was difficult because I had to make some tough decisions about what materials to include and what to leave out. Based on my own thinking and input from colleagues and students since that time, I decided to write a textbook on petrology and leave out mineralogy altogether. The result is the present textbook. It was anything but easy to write this book.

Petrophysics is the study of rock properties and their interactions with fluids (gases, liquid hydrocarbons and aqueous solutions). Because petroleum reservoir rocks must have porosity and permeability, we are most interested in the properties of porous and permeable rocks. The purpose of this text is to provide a basic understanding of the physical properties of permeable geologic rocks and the interactions of the various fluids with their interstitial surfaces. Particular emphasis is placed on the transport properties of the rocks for single phase and multiphase flow. <...>

This book has been written for those studying petroleum geology or engineering, for whom the role of the petrophysicist can become a lucrative and satisfying career. The handbook will be equally useful to students and practioners of environmental science and hydrogeology, where the understanding of groundwater flow is an important part of their technical remit.