An ROA award is recommended to facilitate the participation of W. Conrad (SUNY-New Paltz) in a current research project of J. Rubenstone (Lamont-Doherty Geological Observatory). The award will make it possible for Dr. Conrad, a teacher at a predominantly undergraduate institution to conduct research at a well-equipped research institute. The research concerns the origin of garnet-bearing trondhjemites, an uncommon rock type, intruded into a Cretaceous subduction zone in southern Alaska. Petrologic and electron microprobe investigations will be conducted to determine which of the following hypotheses is correct: (1) trondhjemites originate by fractionation or partial melting of tonulitic magmas with subsequent contamination by country rocks, or (2) trondhjemites are formed by partial melting of graywacke sediments, better understanding of peraluminous magmatism at continental margins.
