9705858 Brown This proposal addresses the question of how granitic melt migrates through the crust in orogenic belts. The PI will investigate the relationship between style of deformation, amount of strain and melt migration pathways. Geochemical data will be obtained to test whether melt transfer routes established on the basis of field observations are traced by contemporaneous granite. The objectives are: to determine the age of crystallization of melt within migmatites and crystallization of granite the occurs in map-scale bodies; to evaluate melt loss and/or melt gain using whole-rock geochemical data; to evaluate possible genetic relationships between granite at various scales by using precise REE data, and Nd isotope data; and to evaluate the metamorphic peak grade profile and possible late orogenic movement across high-strain zones utilizing geothermometry and Rb-Sr thermochronolgy. Results will contribute tot he development of realistic models for melt segregation during crustal anatexis and magma migration from a source region to the level of emplacement as a pluton.
