Page 14 - Geology of Carbonate Reservoirs

PREFACE

This is a book on the geology of hydrocarbon reservoirs in carbonate rocks. Although
it is written for petroleum geologists, geophysicists, and engineers, it can be useful
as a reference for hydrogeologists and environmental geologists because reservoirs

and aquifers differ only in the fluids they contain. Environmental geoscientists
interested in contaminant transport or hazardous waste disposal also need to know

about porosity (capacity to store) and permeability (capacity to flow) of subsurface

formations. The first two chapters focus on definitions and on rock properties that

infl uence fluid movement. The third chapter focuses on reservoir properties — the
interaction between rocks and fl uids — and how rock properties infl uence saturation,
wettability, capillarity, capillary pressure, and reservoir “ quality. ” Although carbon-
ate rocks differ in many ways from siliciclastic rocks, the laws of physics that govern

fluid movement in terrigenous sandstones also govern fluid behavior in carbonates;
therefore many of the principles discussed in this text are applicable to reservoirs
and aquifers in any porous and permeable rock. There are fundamental differences
between carbonates and siliciclastic rocks that will be emphasized thoughout, and
knowing those differences can be used to advantage in exploration, development,
and management of reservoirs and aquifers.
This book evolved from my graduate course on carbonate reservoirs at Texas
A & M University. It is written as a textbook for geologists, engineers, and geophysi-
cists in graduate and upper - level undergraduate courses. I hope it may also be useful
for continuing education courses and as a reference book for industry professionals,
especially for those who are not experts on carbonate rocks and reservoirs. It is not
easy to write a survey of this subject in about 300 pages with a limited number of
illustrations; consequently, this book emphasizes only fundamental principles. The
vast literature on carbonate sedimentology, stratigraphy, geochemistry, and petrog-
raphy makes it impractical if not impossible to include an extensive bibliography
on all of those subjects. I did not include much material on borehole logging and
seismology because they require lengthy explanations with examples that exceed

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