This project is designed to investigate the petrogenesis of anorthosite-jotunite-mangerite rocks from the Grenville Province of Canada. Suites of rocks from the St. Urbain, Labrieville, and Morin regions will be investigated through integrated field, petrological, and geochemical studies. The results should elucidate the nature of parental magmas and differentiation mechanisms of massif anorthosites and associated mangerites and the significance and origin of associated mafic, oxide-rich lithologies (jotunites) and Fe- Ti oxide ore deposits.