Many improvements have occurred in the seismic method since the publication of the first edition in 1982. Concepts that were of academic concern then have since become practical tools and some of the new concepts we have added may become tomorrow's tools.

We want this book to be a reference work as well as a textbook and guide for practicing geophysicists. These three objectives are not always compatible and readers will often skip over portions that do not fit their current needs, hopefully later referring back to skipped portions. For those readers who do skip about, we have cross-referenced sections, equations, and figures. For those who are rusty with their mathematics, we express concepts in words as well as by equations.

Our special interest is in the interpretation of geophysical data, but an interpreter needs to have a thorough understanding of geophysical principles in order to determine the validity of his data and the possibility that features he sees are artifacts of acquisition or processing. To this end, we have tried to emphasize seismic fundamentals.

We give a systematic derivation of relationships from first principles, except for a few cases where the derivations are excessively lengthy or involve higher mathematics, in which instances we refer the reader to other sources. As the preface to our first edition states, “A reader willing to take the mathematics on faith should be able to jump over the equations and still see the implications of the mathematical conclusions, which we have endeavored to explain in words rather than merely letting the equations speak for themselves.