Douglas W. Hilchie originally published this book in 1979 to fill a need at that time; there was no book dedicated to analysis and interpretation of wireline logs run in wells drilled prior to 1958. Today, many oil and gas fields in the world that were drilled before 1958 are still producing. Current operators of those wells have lost the opportunity to learn proven methods of interpretation of log suites and logging-tool technology of that vintage.
This book contains charts for rapid log interpretation generated by companies that have long been out of business. In reprinting Dr. Hilchie’s benchmark text, we include the best-quality figures available from the originals. We believe in all cases that the quality is sufficient for you to use them in evaluating your wells.
Although Dr. Hilchie has been semiretired since 2001, he continues to reflect on the challenges of "getting more information out of old logging suites." Perhaps in his more relaxed years, he will write his next definitive book on interpretation of old electrical logs 19581980!
We owe our gratitude to Dr. Hilchie for his efforts in producing this classic publication, as well as for his years of dedicated mentoring and instruction in the industry. Universities, logging companies, and integrated energy companies have claimed him as an employee and contributor, but the industry claims him as a dedicated teacher. To Dr. Hilchie, we extend our deepest appreciation. May this book, his contribution, help you in your pursuit of the hidden target — oil and gas!
PREFACE TO THE REPRINTED EDITION
Old (pre-1958) electrical logs comprise as much as 40% of the well-log data in oil and gas company files. Books and technical papers related to these unique well logs are very limited and, in most cases, almost unobtainable in today’s world. With fewer log analysts and petrophysicists understanding the analysis of these logs, it has become more important that geologists using this data obtain a better knowledge. Today, even though interpretation of well-log data is at best semiquantitative, experience has shown that in 7080% of definitive interpretations, recompletion of these wells produces commercial hydrocarbon production.
Geologists should understand that interpretation of these logs has improved significantly in the last 50 years. It should also be noted that economics and production techniques have changed significantly in that time period. What may have been overlooked or ignored in past times is now economically viable.
Douglas W. Hilchie