Linking Deep Earth Processes and Surface Systems
July 2, 2020, Dr. Sally Gibson Webinar
Abstract: My research is inspired by a passion to understand how large-scale geodynamic processes in Earth’s deep interior impact on its surface systems. This has involved petrographic and geochemical analysis of samples collected during field campaigns in Large Igneous Provinces (Paraná-Etendeka, Deccan and Tertiary North Atlantic Igneous Provinces), continental rift zones (Rio Grande, Baikal, East Africa) and ocean islands (Galápagos and Trindade) together with studies of mantle xenoliths and kimberlites. Much of the ongoing activities of my research group unify these long-held interests, and focus oncombining micro-scale observations with in-situ analyses of volatiles in basalts and mantle xenoliths to improve constraints on the global cycling of elements that are vital to life and our planet’s habitability. One of the major goals is to quantify the concentrations and distributions of H 2 O, F, Cl, Li, and CO 2 in Earth’s subcontinental mantle so that we can place more robust constraints on the role that this large and ancient reservoir plays in modulating the flux of volatiles from its deep interior to its atmosphere via volcanism. Our findings suggest that the re-mobilisation of volatiles stored in pyroxene-rich regions of the lithospheric mantle — e.g. during the formation of Large Igneous Provinces in the geological past and continental rift zones at the present-day — may be a particularly important driver of environmental change.