Other
Scientific paper
Oct 1995
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1995gecoa..59.4105l&link_type=abstract
Geochimica et Cosmochimica Acta, vol. 59, Issue 19, pp.4105-4110
Other
7
Scientific paper
Yttrium zoning has been measured in garnets from The Straits Schist, Connecticut, USA, using the Synchrotron X-ray fluorescence (SXRF) microprobe. SXRF compositional maps for Mn and Fe show that the major elements are concentrically zoned about the gannet core in the classic bell-shaped profiles considered indicative of growth zoning. Yttrium, however, displays oscillatory zoning which varies three orders of magnitude in abundance, from about 3 to 4000 ppm, and is correlated with textural zoning in garnet. The major element abundances, by contrast, display no visible inflection related to textural zoning. At this time it is not possible to unequivocally identify the mechanism which has produced this oscillatory zoning. Most likely this reflects either the breakdown of Y-enriched phases, changes in the rate of garnet growth with time, or changes in the effective Y concentration of matrix phases due to breakdown and reprecipitation of garnet as the equilibrium reactions involving gannet change. This study demonstrates that the SXRF microprobe provides excellent, spatially resolved compositional maps for trace elements in porphyroblasts, something other analytical techniques have been unable to do. It also suggests that the diffusion rates for Y in garnet are probably significantly slower than those for major cations such as Mn, Fe, Mg, and Ca. As a result trace element mapping potentially provides a clearer record of the reaction history of the rock, provides details of how chemical zoning in garnet is produced, and allows evaluation of assumptions about chemical equilibrium between minerals.
No associations
LandOfFree
Yttrium zoning in metamorphic garnets does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Yttrium zoning in metamorphic garnets, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Yttrium zoning in metamorphic garnets will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1353510