The purpose of this book it to present the structural data and informa-
tion which petroleum geologists and students of petroleum geology need
in order to practice their profession. Petroleum geologists are naturally
interested in many aspects of structural geology which are not related to
prospecting for or producing petroleum. However, limitations of space
prevent discussion of those aspects of structural geology which have no
bearing on oil finding.

Although petroleum geologists are in a profession with a practical
objective, too great an emphasis on what is immediately useful would
make any treatment of structural geology less valuable. In writing the
chapters which follow, the author has kept in mind that the main objec-
tive is to give a thorough understanding of the subject. In many cases
this may be achieved by forgetting for the moment the practical
applications.

This book is intended to be used with the author's previous publication,
"Principles of Petroleum Geology," and each of the two books is designed
to cover subject matter which the other omits. It is hoped that this
planned treatment of two related subjects may permit a better integra-
tion of courses in petroleum geology and structural geology.

Acknowledgments are due to Travis J. Parker for a critical reading of
the manuscript. The author would like to express especial gratitude to
his wife, Leonore K. Russell, for a critical reading of the manuscript and
for aid in preparing the references.

WILLIAM L. RUSSEL

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