9526269 Patchett This grant provide partial support of the costs of acquiring a new thermal ionization mass spectrometer (TIMS) with multiple collectors and ion counting capabilities which will used for isotopic research at the University of Arizona's Department of Geosciences. Specifically, the new TIMS will complement an existing VG-354 TIMS purchased entirely with University of Arizona funds in 1983 that is presently oversubscribed and is beginning to show degradation, particularly with regard to measurements of Strontium isotope ratios. Thus the older TIMS will be used primarily for analyses of U-Pb, Lu-Hf and Sm-Nd isotopes in studies of tectonics and crustal genesis while the new TIMS would be largely used for research utilizing Sr isotopes in studies of Himalayan tectonics and the use of 87Sr/86Sr in lacustrine carbonates as a proxy for paleolake levels. ***