Why another book on seismology? Several excellent texts already exist that cover most parts of the field. None, however, is ideal for the purposes of an introductory class. Most simply present far more material than can be adequately covered in a single quarter or semester. My goal for this book is to produce a readable, concise introduction to the quantitative aspects of seismology that is designed specifically for classroom instruction. The result is not as rigorous or comprehensive as Aki and Richards (1980) or Lay and Wallace (1995), but I hope that it is more suited for teaching an overview of seismology within a limited time period.

To quicken the pace, many results are described without detailed proofs or derivations of equations. In these cases, the reader is usually referred to Aki and Richards or other sources for more complete explanations. Generally I have attempted to provide practical descriptions of the main concepts and how they are used to study Earth structure. Some knowledge of physics and vector calculus is assumed, but in an effort to make the book self-contained most of the key concepts are reviewed in the Appendices.

Any book to some extent reflects the prejudices of its author. In this regard, I have perhaps included more material on ray theory and body wave travel times, and less on surface waves and normal modes, than a truly balanced book would require.