What caused melting at Great Falls? At the highest grades of metamorphism exposed along the Great Falls section of the Potomac River, migmatite is juxtaposed against amphibolite. Deformation has obscured the original igneous contact relationships. This project would use laser ablation ICP-MS to determine the igneous and metamorphic ages of the rocks types and thus determine whether the amphibolite could represent intrusive basaltic magma that heated the metapelitic country rocks and caused their melting.

Supervisors: Roberta Rudnick, Bill McDonough