Mark Hoggard ""Dynamic topography: Interactions between mantle convection, landscape evolution, sedimentary basins, and the pattern of oceanic circulation"
Dr. Mark Hoggard The Australian National University will discuss dynamic topography: Interactions between mantle convection, landscape evolution, sedimentary basins, and the pattern of oceanic circulation. Mantle convection causes transient vertical motions of Earth's surface, known as dynamic topography, that are increasingly being invoked to explain large-scale uplift and denudation of continents, the stratigraphic architecture of sedimentary basins, and even paleoclimatic events. There remains, however, considerable mismatch between observational constraints and predictive models of mantle convection concerning both the present-day pattern of dynamic topography and the rate at which it evolves. This disagreement impedes our ability to further investigate the role that dynamic topography plays in shaping the geological record. In this seminar, I will give an overview of my work both on extracting high precision observational constraints of dynamic topography and on reconciling these observations with revised predictive models of global mantle flow. Agreement between models and observations at the present day is now sufficiently robust that we can, for the first time, explore more accurate reconstructions of the temporal evolution of Cenozoic dynamic topography. As this work progresses, we continue to uncover evidence for a highly dynamic upper mantle that plays a substantial role in modulating processes as diverse as volcanism, sediment routing systems, and the evolution of paleoclimate.