9707119 Farley This grant provides $149,996 as three years partial salary support for a technician to oversee operation and maintenance and to provide training to new users of the Caltech Noble gas geochemistry laboratory. The addition of a skilled technician to this facility will allow the PI to continue development of novel and exciting techniques utilizing rare gas geochemistry to elucidate fundamental problems in the Earth sciences. Specific examples of the PI's accomplishments to date include, the PI's development of apatite helium thermochronology. This technique utilizes known diffusional rates of 4He from decay of uranium and thorium series nuclides in apatite to constrain cooling histories. Additionally, the PI's discovery of correlations between the flux of extraterrestrial helium to seafloor sediments and global climate and faunal changes are potentially significant for our understanding of the linkages between the Earth's climate and extraterrestrial factors. ***
