Well Logging for Earth Scientists (Second Edition) / ГИС для геологов и геофизиков (второе издание)

Well logging lies at the intersection of applied geophysics, petroleum and geotechnical engineering. It has its roots in the tentative electrical measurements in well bores which were made by the Schlumberger brothers some 80 years ago in the earliest days of systematic petroleum exploration. Today, a variety of specialized instruments is used to obtain measurements from the borehole during, as well as after, the drilling process. This readable and authoritative treatment of the physics of these measurements dispels the "black magic" of well log interpretation by relating them, including those obtained by the latest generation of tools, to rock physics. It offers a thorough exposé of the physical basis of borehole geophysical measurements, as well as an introduction to practical petrophysics -- extracting desired properties from well log measurements. Twenty years ago, the objectives of the first edition of this book were numerous and ambitious: to demystify the process of well log analysis; to examine the physical basis of the multitude of geophysical measurements known collectively as well logging; to clearly lay out the assumptions and approximations routinely used to extract petrophysical information from these geophysical measurements; to expose the vast range of well logging instrumentation and techniques to the larger geophysical community. Finally, there was the important goal of providing a textbook for university and graduate students in Geophysics and Petroleum Engineering, where none suitable had been available before. What’s different twenty years later? First of all, Well Logging for Earth Scientists is long out of print. The petroleum industry, the major consumer of the geophysical information known as well logging, has changed enormously: technical staffs have been slashed, and hydrocarbons have become increasingly harder to locate, quantify, and produce. In addition, new techniques of drilling high deviation or horizontal wells have engendered a whole new family of measurement devices incorporated into the drilling string that may be used routinely or in situations where access by traditional “wireline” instruments is difficult or impossible. Petroleum deposits are becoming scarce and demand is steadily increasing. Massive corporate restructuring and the “graying” of the workforce have caused the technical competence involved in the search and exploitation of petroleum to become scarce. Although we are only attempting to address this latter scarcity with our textbook, the objectives are still ambitious In this thorough updating of the text, we have attempted to include all of the new logging measurement technology developed in the last twenty years and to expand the petrophysical applications of the measurements. As in the first edition, we are primarily concerned with logging techniques that lead to formation evaluation, but mention a few other applications where appropriate. We also trace the historical

development of the technology as a means of better understanding it. Throughout, large sections of the text have been set in italics, which may be skipped by the casual reader. These detailed sections may be of more interest to researchers. The goals of providing a graduate level textbook as well as a useful handbook for any practicing earth scientist (geophysicist, geologist, petroleum engineer, petrophysicist) remain.