March 4, 2022 at 10:30am CST
Host: Thorsten Becker
Title: Surface responses to deep Earth dynamics: Insights from landscape evolution modeling
Abstract: Over Earth’s geologic history, our surface environment has been constantly reshaped by climate and tectonic events. Being able to model their interactions in a source-to-sink context provides us a unique way to decipher the dynamics of Earth interior from the geological record. In this talk I will focus on the surface evolution in two tectonic settings with: 1/ a continent moving laterally above a mantle upwelling (i.e., a pulse of dynamic uplift), and 2/ a slab subducting at different dips at a convergent margin. We find that when the continent passes over a mantle upwelling, significant drainage reorganizations are induced, which varies the sediment supply and contributes to the formation of diachronous unconformities along the continental margins. The signal of the uplift pulse is recognized by correlating offshore depositional hiatuses and unconformities. In the second scenario, by varying the dipping of subducting slabs, we found systematic changes in retroarc foreland basin geometry, stratal patterns and controlling subsidence mechanisms. This allowed us to compare with geological observations and to provide implications on the subduction dynamics and orogenic evolution.