Page 5 - The Geological Interpretation of Well Logs

PREFACE

This second edition of a book originally written ten years given. Especial ackowledgement must go to Gavin
ago has a great deal of new material, new chapters and Cameron for his contributions in the dipmeter field.
previous chapters much modified. But the philosophy These feature in the dedicated dipmeter chapter, new in
and format and approximately half the text are the same. this edition, which leads naturally to a chapter on the
The book describes, discusses and illustrates with many exciting, new, image logs.
real examples, the interpretation of well logs for geolog- The manuscript has been significantly improved by
ical ends. Basic tool design is an essential inclusion, but suggestions and criticisms by specialists in a number of
petrophysics, that is the use of logs for quantifying fields: dipmeter and image logging, Robert Trice; log-
hydrocarbons, is only very briefly considered. This was ging mechanics, Peter Elkington; sequence stratigraphy,
the case in the first, widely sold edition. John Underhill; and Tertiary geology, Robert Knox. Data
In the intervening years there have been many and discussion have been provided by Amerada Hess
significant changes. The PC has replaced the mainframe UK Ltd, Western Adas, Halliburton, Schlumberger, BPB
and the personal use of a computer for log analysis is and the Universities of London and Liverpool: they all
now assumed: in the previous edition it was not even receive my grateful thanks and recognition. But this new
considered. There has been a revolution in logging tool edition would not have been possible without the huge
design. Tools today incorporate downhole processing, efforts made by the team at Whittles Publishing. They
and logging signals are digital. This has sourced new have achieved what I consider to be a superb presentation
tools, which are described, as also are new versions of which makes the book both practical and agreeable to
old tools. For this, the straightforward descriptive format Jook at: for this my considerable thanks.
used originally has been used again. Not only has log- Journalists who write books are generally unsuccess-
ging advanced, so have geological ideas, notably with ful; their style is too obviously self-conscious. Most
the advent of sequence stratigraphy. Using both the old scientists who write suffer from the opposite; content is
and the newer logs for sub-surface sequence stratigraphy the only consideration (there are, of course, obvious
is discussed: the possibilities are exciting. exceptions). To most scientists, prose is like make up: it
Although the new is attention grabbing, the old basic is there to embellish (hide, exaggerate, enhance) the truth.
logs still form the foundation to a routine geological well Since science prefers the truthful truth, prose is neglected.
evaluation. This edition, therefore, combines the well But most women will willingly admit that embellishing
established with the newer and more experimental. But the truth has its benefits. And I would agree. In no way will
throughout, it is the geological content of the logs that is there be an attempt to embellish the truth in this book but
important: lithology, facies, depositional environment, I do admit to an admiration for those who write well. J
sequence stratigraphy, correlation and more. Judging have done my conscious best to be clear; with jargon ta
from the past, the book best serves the purpose of those the minimum.
beginning to acquaint themselves with logs, in industry Many books are dedicated to wives or mothers or chil-
or academia, and those who do not use logs all the time dren or even cats. This is a queer habit. And quite silly. I
and like to use the book as an occasional reference. love my children but they have nothing to do with this
I still feel that I owe an early debt to my old colleagues book: they did their unconscious best to impede it. The
from CFP (Total) and to Oberto Serva, then Elf but best introduction to a book I have ever read is a quote
recently retired from Schlumberger. Newer ideas have (Barrow, 1992) from Groucho Marx: ‘From the moment
come from industry colleagues, many in the consulting I picked up your book wil [laid it down, I was convulsed
world, and the feedback from many industry courses with laughter. Some day | intend reading it.

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