Reflecting the changes in knowledge of the earth's chemisty, this revision is more quantitative, gives more attention to environmental issues, and places more emphasis on the application of geochemistry to geological problems than its predecessor. Using examples from actual field and laboratory studies, the authors aim to make their subject an exciting area of research for students who are chemically inclined. There is expanded coverage of kinetics, surface chemistry and the geochemistry of isotopes. A new appendix includes fully-worked problems with answers.