A Late Jurassic Mafic Pluton in Newfoundland
A small alkaline ultramafic intrusion in central Newfoundland is dated as 135 ± 8 m.y. old and 139 ± 9 m.y. old by the K–Ar method on biotite. This is the first known Mesozoic pluton (aside from dikes) in Newfoundland. The occurrence, composition and age of the pluton and associated igneous rocks is similiar to, and perhaps related in origin to, igneous rocks found in the Monteregian Hills of Quebec and other areas in eastern North America.