Doctor of Philosophy in Geochemistry - Isotope Geochemistry

Geochemistry is the study of the chemical and structural composition and evolution of Earth and its component parts, including the atmosphere, hydrosphere, crust, mantle, and core, as well as extraterrestrial matter, such as meteorites and comets, other planets, the sun, and distant stars. It concerns itself with the distribution and migration of elements within the Earth and its atmosphere. Over time, geochemistry has evolved from a descriptive science to one increasingly concerned with the mechanisms behind its observations.Geochemistry today is diversified into many subfields, including aqueous geochemistry, cosmochemistry, inorganic geochemistry, isotope geochemistry, organic geochemistry, and trace-element geochemistry. Since most geological processes involve chemical reactions, geochemistry and geochemical data are also used to explain many of these processes in other areas of the geosciences.At Caltech GPS, geochemistry has been used since 1952 to study the distribution of chemical elements in the Earth and the solar system, to develop methods to date earth and solar system processes, to discover and observe the chemical composition of terrestrial and extraterrestrial materials, and to study chemical reactions in the interior of the Earth as well as its surface and in the solar system outside of the Earth. Caltech has had a long history in both stable and radiogenic isotope geochemistry including Clair Patterson's first accurate determination of the age of planet earth. Currently, we have active programs in the following areas.

Applicants must have completed a bachelor's degree or the equivalent before beginning graduate study. Applicants who already hold a Ph.D. degree will not be considered for a second Ph.D. degree. Transcripts from each college or university attended, three letters of recommendation, a CV, and the applicant's statement of purpose are required components of the application and are carefully and equally weighed during the evaluation process.



There is no minimum requirement for the English proficiency exams. However, all new students who have had limited instruction in English will participate in a one-on-one English evaluation with the ESL instructor during Orientation and may be asked to enroll in an English as a Second Language (ESL) course.