The roots of sedimentology and stratigraphy extend back to the 16th century; however, these disciplines are still growing and changing. Geologists continue to "fine tune" sedimentologic and stratigraphic concepts through a variety of research avenues and by using an array of increasingly sophisticated research tools. T he result is a continuous outpouring of fresh data and new ideas. In fact, it is becoming increasingly difficult to keep abreast of the flood of new information appearing in the geological literature. A glance through recent issues of a well-known sedimentology journal reveals important new papers on sedimentation and tectonics, depositional systems, carbonates, biosedimentology, diageneis, provenance, geochemistry, sediment transport and sedimentary structures, stratigraphic architecture, chronostratigraphy, numerical modeling, paleoclimatology, sequence stratigraphy, and basin analysis-to name but a few research areas. <...>

A second edition of this textbook, first published 17 years ago, is a wonderful opportunity to review its contents and improve its pedagogical orientation, in view of the many comments and interactions received, teaching experience, and experimental progress in seismology over the intervening years. Seismology is the science of earthquakes, which are both natural disasters profoundly affecting human lives, and a subject of study through application of the principles of the physical sciences.

As soon as the second edition of Principles of Soil Chemistry appeared, it was sought after by many scholars, students, professionals, and scientists interested in the chemistry of soils. It was chosen as the textbook at the University of Georgia for teaching the senior-level undergraduate and graduate course in soil chemistry. It has been used as a textbook in soil chemistry at the University of California, Davis, and other universities in the United States. Because of its simple language and style, which avoid making problems more complex than needed without sacrificing scientific standards, the book is particularly appealing as a textbook in many universities overseas. The first edition of Principles of Soil Chemistry was translated in Indonesian and published by the University of Gadjah Mada Press, Yogyakarta, under the title Dasar-Dasar Kimia Tanah, which soon sold out and is out of press. I was invited to teach Soil Chemistry and Soil Genesis courses for a semester in 1996 at the University of Andalas, Padang, Sumatra, Indonesia, and in 1995 at the Universidad Nacional del Sur, Bahia Blanca, Argentina, where my first and then the second edition were adopted as the main textbook for these courses.

Stratigraphy is one of the most demanding, fundamental, and interesting of geologic disciplines. It tries to reconstruct history with a few basic principles, requires both careful observation and wide-ranging imagination, and involves many individually fascinating subdisciplines. Yet, as the quotation above shows, this is not how it appears to many people. Stratigraphy has a poor image because it is sometimes presented only as a way of classifying and organizing strata with “codes.”