9418228 Kelemen The study of shallow mantle peridotite provides a window into processes of melt extraction, melt transport, and deformation. Field studies of the relationship between physical properties of the mantle and melt distribution provide a critical link between constraints provided by laboratory experiments, hand specimen geochemistry, and large scale geophysical observations. This is a field investigation of textural, modal and compositional variation in the shallow mantle sections of the Josephine and Trinity ophiolites (SW Oregon and N California). Determination of grain size, grain size distribution, grain shape, and crystallographic fabric across igneous reaction zones in the peridotite, in combination with detailed studies of compositional variation, will provide constraints on the melt/rock ratio, mechanisms of recrystallization during localized deformation, and the nature of melt transport through these zones.
