Stable Isotopes Rare Gas Isotopes Radiogenic Isotopes Isotopic Tracers   Geochemistry Home GPS Home Caltech Home	ISOTOPE GEOCHEMISTRY   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.   Stable Isotopes   Professors Eiler and Taylor operate stable isotope laboratories and conduct research into igneous petrology, planetary surfaces, meteorites, geothermometry, paleo-climate, and analytical methods.   Rare Gas Isotopes   Professor Farley has developed a method for using the helium-4 generated from the decay of uranium and thorium in apatite to study the thermal history of the host rock.  From these studies, he is able to establish the rate of mountain range exhumation. He also uses the concentrations of helium-3 in seafloor sediments to determine the accretion rate of cosmic dust back through time.  Striking variations in the accretion rate occur over time.   Radiogenic Isotopes   Professor Wasserburg's group is concerned with dating and isotopic phenomena in the solar nebula, the early solar system, meteroites, and mantle rocks.  Additional methods have been developed for dating comparatively recent events in geological time.   Isotopic Tracers in the Environment   Professor Wasserburg's group has developed methods to study the transport of heavy metals in the oceans and rivers.   back to top | Geochemistry Home | GPS Home | Caltech Home