This monograph is prepared after spending my 40+ year career in the upstream oil and gas industry as a reservoir engineer. This included a decade in the upstream research-and-development department of ARCO, a major US oil company, followed by decades in a variety of technical assignments that allowed me to delve into the fundamentals and details of a wide range of reservoir engineering and related issues, often in dispute in technical arbitrations and litigations. I had the fortunate situation to work numerical reservoir simulator applications using the variety of numerical simulators being developed during the 1970s when the computing horsepower was limited and reservoir models were typically limited to hundreds to a few thousand gridblocks. Because of these constraints, I could review the data input, model code, computer output, and also understand the interactions of the physical laws, mathematical code, and simple geological models in ways that are impossible with modern multimillion cell, geocellular, and reservoir simulation models typically now used to describe and analyze oil reservoirs.

During my career I have interacted with hundreds of reservoir engineers, oilfield operations personnel, geologists, geochemists, and university academics and researchers. These interactions ranged from being on multiyear, multicompany technical teams to routine hallway and cafeteria technical discussions to attending technical presentations at many SPE technical meetings. I want to thank all of these individuals because these environments were stimulating for offering alternative ways to view various technical issues and, at times, challenging conventional technical wisdom.

There are some people who significantly contributed to my efforts as I prepared this monograph. These individuals and their roles are mentioned as follows.

I prepared Chapter 4—Geology only after lengthy conversations with several geologists with whom I have worked for several decades and by drawing on their libraries of geological reference books. Dr. Robert S. “Bo” Tye aided my efforts through numerous discussions and by editing my drafts of this chapter and offering revisions, almost all of which I accepted. Professor Roger M. Slatt, Gungoll Family Chair Professor Petroleum Geology and Geophysics and Director, Institute of Reservoir Characterization, University of Oklahoma provided me input primarily by means of his 2006 book Stratigraphic Reservoir Characterization for Petroleum Geologists, Geophysicists, and Engineers (Slatt 2006), which I often quote and from which I used various figures. Drs. Shirley P. Dutton and R.G. “Bob” Loucks, both Senior Research Scientists with the Bureau of Economic Geology, The University of Texas at Austin, and Dr. A.H. “Art” Saller provided the sandstone and carbonate thin section and scanning electron microscope microphotographs and their descriptions included with this chapter.

I would also like to acknowledge Mr. John M. Dacy, Technical Director at Core Laboratories LP, Houston, Texas, with whom I interacted on the many details of various rock property measurements described in Chapter 6—Quantification of Rock Parameters for Waterflood Calculations. During the past thirty years, John has been a valuable resource whenever I needed the details of routine core analysis or special core analysis laboratory testing methods and equipment. Also, John and his coworkers provided me several photographs, schematics, and testing ranges included in this chapter.

Ed Holstein and Dennis Beliveau, reservoir engineers with long careers with Exxon and Shell, respectively, and as reservoir engineering consultants more recently, were sounding boards through emails and phone calls during the past three years as I prepared outlines, drafts, and desired general technical discussions while this monograph was assembled. I have had the privilege of working with both on various technical projects and on SPE committees during the past three decades. They also provided me technical details about several of the oil reservoirs discussed in Chapter 12—Waterflood Case Studies. Also, Dennis provided the spreadsheet files concerning the Canadian viscous oil waterfloods discussed in his SPE paper “Waterflooding Viscous Oil Reservoirs” (Believau 2009) from which the plots included in Appendix G were prepared.

SPE headquarters staff, particularly Mattie Tanner and Jennifer Wegman, provided needed guidance to aid me and deal with the issues of a reservoir engineer preparing a publishable manuscript, all the details regarding figures, tables, and referencing past technical publications, and editing my manuscript revisions after incorporating the technical reviewers’ comments.

SPE would like to thank Shaya Movafaghian for his generous contributions to the oversight of this book project on behalf of the Books Development Committee. We appreciate his contributions in working with the author and ensuring that timelines and quality standards were upheld through the process.