Collaborative Research: Emplacement of the Ferrar Mafic Igneous Province: A Pilot Study of Intrusive Architecture and Flow Directions in Southern Victoria Land

Southern Connecticut State University, New Haven CT

Investigators

Abstract

This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, provides funds for a study to investigate the Ferrar magmatic province toward understanding of the formation of this province and its role in the breakup of the Gondwana supercontinent. The dispersal of Gondwana represents one of the largest supercontinent breakup events in the Phanerozoic. Breakup was associated with the emplacement of a very large Jurassic mafic igneous province extending across the Karoo (southern Africa), Ferrar (Antarctica), and Tasman (Australia) regions, comprising continental flood basalts and extensive intrusive dolerites. Models linking development of the >3,000 km Ferrar province to a mantle plume, a major magma conduit, or multiple sources, make testable predictions about magma transport patterns within the Ferrar province. This project is a pilot study using several different techniques aimed at evaluating these models and providing a greater understanding of the emplacement mechanisms, flow directions, and magmatic architecture associated with the Ferrar mafic intrusive province in southern Victoria Land. Our research tools will include mapping intrusive geometry based on structural field studies and geochemical correlation techniques. Magma flow directions within the intrusive complex will be evaluated using anisotropy of magnetic susceptibility, and mesoscopic and petrofabric flow indicators. These results will help resolve outstanding questions concerning the geometry, propagation, and flow patterns of magma during emplacement of sills and dikes in mafic large igneous provinces. It will also provide a deeper understanding of the relationships between mantle plumes, basaltic magmatism and continental breakup.