IGPP is pleased to invite you to join its Winter 2022 Seminar Series presentation featuring Ludwig Maximillians Universitat's Ingo Stotz. Dr. Stotz's talk, "Theoretical estimates of upper mantle flow and their link to horizontal and vertical plate motions" will be available via Zoom on Tuesday, January 25, 2022, starting at 12:00pm. Zoom: https://ucsd.zoom.us/j/95389952214?pwd=ODBVRG52Sk11L0JKUk9iQ0FsRHdMQT09. Password: Mantle
Date: Tuesday, January 25, 2022
Time: 12:00 pm, Pacific Time
Note: This meeting will be recorded. Please make sure that you are comfortable with this before registering.
Abstract: Earth's surface moves in response to a combination of tectonic forces from the thermally convective mantle and plate boundary forces. Plate motion changes are increasingly well documented in the geologic record and they hold important constraints. However, the underlying forces that initiate such plate motion changes remain poorly understood. Here, I will present numerical and analytical calculations that help to better understand driving and resisting forces of plate tectonics.
I have developed a novel 3-D spherical numerical scheme of mantle and lithosphere dynamics, aiming to exploit information of past plate motion changes in quantitative terms. In order to validate the models and single out those most representative of the recent tectonic evolution of Earth, I compare the global plate velocity output of my models to global plate kinematic reconstructions. In particular, numerical results indicate that mantle convection plays an active role in driving Pacific plate motion through pressure driven upper mantle flow. Additionally, over the past years a pressure driven, so-called Poiseuille flow, model for upper mantle flux in the asthenosphere has gained increasing geodynamic attention–for a number of fluid dynamic arguments. This elegantly simple model makes a powerful testable prediction: Plate motion changes should coincide with regional scale mantle convection induced elevation changes. For this the histories of large scale vertical lithosphere motion recorded in the sedimentary record holds important information. Altogether, theoretical and observational constrains provide powerful insights for geodynamic forward and inverse models of past mantle convection.