MT Survey of the Kaapvaal Craton

Woods Hole Oceanographic Institution, Woods Hole MA

Investigators

Abstract

0309584 Evans Central to our understanding of continental evolution is providing a better understanding of how the mantle participated in the growth and stabilization of ancient cratons. This is a project involving a series of magnetotelluric (MT) transects crossing the Kaapvaal craton in southern Africa and its bounding terranes, probing the crust, lithosphere and asthenosphere with sufficient station density to provide a 3D cross sectional electrical image of the craton. The electrical structure of the mantle is impacted by thermal structure, by the presence of conducting phases such as graphite and dissolved hydrogen, and where applicable, by interconnected melt. Many of the processes thought to be involved in continental accretion result in characteristic geometries and structures that MT surveys can help identify. The experiment is an international collaboration, involving US and Canadian PIs working with scientists in Africa and also involving colleagues from Germany. The PIs will collaborate closely with South African academics and students and they will train them in MT data acquisition, data processing and modeling. The project has been motivated by a previous multi-disciplinary Continental Dynamics project to study the structure and evolution of the Kaapvaal craton. The PIs will host a workshop in the second year of the project at which they will integrate their results with those of the previous Kaapvaal project.