Ken Farley is the W.M. Keck Foundation Professor of Geochemistry in the Division of Geological and Planetary Sciences at the California Institute of Technology. His research centers on development and application of geochemistry techniques, especially involving isotopes of the noble gases, to a wide range of terrestrial and solar system questions. Specific areas of interest include geochronology of both Earth and Mars, the geochemical evolution of the Earth, and the behavior of noble gases in minerals. He is currently a participating scientist on the Mars Science Laboratory mission and is project scientist for the Mars 2020 Science Rover mission. Farley was born in Los Angeles, California in 1964. He received a bachelor of science degree in chemistry from Yale University in 1986 and a doctorate in Earth Science from the Scripps Institution of Oceanography, University of California San Diego, in 1991. He began his professorial career at Caltech, in 1993. He became Chair of the Division of Geological and Planetary Sciences in 2004.

Research Interests

Farley is a technique-oriented geochemist focusing on the use of the noble gases, mainly helium isotopes, as tracers and chronometers of terrestrial and extraterrestrial processes. Much of the development and calibration of the (U-Th)/He dating system now commonly used to establish the cooling and exhumation history of rocks was developed in Farley's lab. A second long-term effort has shown that the accretion rate of cosmic dust to Earth can be traced by the 3He concentration of marine sediments, and that variations in the flux document major events in the history of the solar system such as comet showers and collisions between asteroids. Additional areas of interest include surface exposure dating and characterization of the geochemical evolution of the Earth as recorded in the isotopic composition of volcanic rocks. On the Mars Science Laboratory mission Farley led an effort to obtain the first radiometric and surface exposure age measurements performed on another planet. He is now project scientist for a NASA Mars mission, planned for launch in 2020, that will prepare samples for possible future return to Earth for intensive study.

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Primary Section

Section 15: Geology