JACUPIRANGITE-SYENITE ASSEMBLAGE BENEATH THE WHITE HILLS PERIDOTITE, NORTHWESTERN NEWFOUNDLAND.

Abstract

An assemblage of alkaline rocks, including jacupirangite, alkaline pyroxenite, hornblende gneiss, and syenitic mylonite, occurs between the White Hills Peridotite and its metamorphic aureole. It was previously mapped as part of the amphibolite unit underlying the peridotite but was recognized by the authors during detailed work on the St. Anthony Complex. In this paper, the geology, mineralogy, petrology, and possible origin of these rocks are discussed in the context of their geological setting within the St. Anthony Complex.