Shuster, David L. and Farley, Kenneth A. and Sisterson, Janet M. and Burnett, Donald S. (2004) Quantifying the diffusion kinetics and spatial distributions of radiogenic ^4He in minerals containing proton-induced ^3He. Earth and Planetary Science Letters, 217 (1-2). pp. 19-32. ISSN 0012-821X. http://resolver.caltech.edu/CaltechAUTHORS:20121119-100729426
Full text is not posted in this repository. Consult Related URLs below.
Use this Persistent URL to link to this item: http://resolver.caltech.edu/CaltechAUTHORS:20121119-100729426
Apatite, titanite and olivine samples were bombarded with a ~ 150 MeV proton beam to produce ~ 10^8 atoms/mg of spallation ^3He. High-precision stepped-heating experiments were then performed in which the artificial ^3He and, for apatite and titanite, the natural radiogenic ^4He were measured to characterize the diffusive behavior of each isotope. Helium-3 diffusion coefficients are in excellent agreement with concurrently and/or previously determined He diffusion coefficients for each mineral. Our results indicate that proton-induced ^3He is uniformly distributed and that radiation damage associated with a proton fluence of ~ 5 x 10^(14) protons/cm^2 does not cause noticeable changes in ^4He diffusion behavior in at least apatite and titanite. Proton-induced ^3He can therefore be used to establish He diffusion coefficients in minerals with insufficient natural helium for analysis or those in which the natural ^4He distribution is inhomogeneous. In addition,step-heating ^4He/^3He analysis of a mineral with a uniform synthetic ^3He concentration provides a means by which a natural ^4He distribution can be determined.
|Additional Information:||© 2003 Elsevier B.V. Received 25 April 2003; received in revised form 18 June 2003; accepted 7 October 2003. We thank T. Schneider, S. Mukhopadhyay and E. Schauble for helpful input, L. Hedges for sample preparation and E. Cascio for his expertise with the irradiation, and two anonymous reviewers. This work was supported by the National Science Foundation and by a N.S.F. Graduate Research Fellowship to D.L.S.[BW]|
|Subject Keywords:||helium; diffusion; thermochronometry; isotope; proton beam; (U–Th)/He|
|Official Citation:||David L Shuster, Kenneth A Farley, Janet M Sisterson, Donald S Burnett, Quantifying the diffusion kinetics and spatial distributions of radiogenic 4He in minerals containing proton-induced 3He, Earth and Planetary Science Letters, Volume 217, Issues 1–2, 1 January 2004, Pages 19-32, ISSN 0012-821X, 10.1016/S0012-821X(03)00594-6. (http://www.sciencedirect.com/science/article/pii/S0012821X03005946)|
|Usage Policy:||No commercial reproduction, distribution, display or performance rights in this work are provided.|
|Deposited By:||Ruth Sustaita|
|Deposited On:||19 Nov 2012 18:25|
|Last Modified:||19 Nov 2012 18:25|
Repository Staff Only: item control page