Published: Sept. 1, 2017
EarthScope Poster

Earth Scope Speaker Series

About

Rebecca Flowers is an Associate Professor in the Department of Geological Sciences at the University of Colorado Boulder. Her research is broadly on problems in continental tectonics, with a particular focus on better understanding the coupling of deeper Earth and surface processes. Flowers directs a (U-Th)/He geochronology lab. She and her group have used (U-Th)/He dating to address questions that include the carving of the Grand Canyon, the burial and erosion history of cratonic interiors, the uplift history of the Rocky Mountains and southern African Plateau, and the impact history of the moon. Her lab also is engaged in a variety of method development efforts on mineral phases not conventionally dated by (U-Th)/He, including perovskite, conodonts, baddeleyite, monazite, garnet, and rutile. Flowers received her BSc degree at the College of William & Mary, her MSc degree at the University of Utah, her PhD at MIT, and spent two years as a postdoctoral scholar at Caltech. She has served on the EarthScope Steering Committee, the AGU Tectonophysics Program Committee, the GSA Student Research Grant review committee, the Board of the GSA Structural Geology & Tectonics Division, and as an instructor at the CIDER (Cooperative Institute for Dynamic Earth Research) Summer Program. Flowers is the lead PI and organizer of the AGeS (Awards for Geochronology Student research) program, which was implemented within the EarthScope program as a new strategy for supporting community access to geochronology data and the scientific expertise of lab personnel.

EarthScope Speaker Series Presentation

Title: Deep-time hypsometric history of the North American continental interior and implications for mantle dynamics

Abstract: Cryptic epeirogenic elevation change in continental interiors is not easily accounted for by plate margin tectonism. Dynamic topography, or elevation change of the Earth’s surface in response to normal traction generated by mantle convection, provides an attractive explanation for such vertical motions. However, despite the increasing sophistication of dynamic modeling efforts, it remains challenging to definitively test the predictions of these models. The North American continental interior was shielded from distal tectonism during the Phanerozoic, making this region an excellent location to isolate the effects of dynamic topography in the rock record. This talk will outline our interdisciplinary strategy to decipher the thickness, spatial extent, and evolution of missing sections of the Phanerozoic stratigraphic record across the North American interior to illuminate the cryptic hypsometric evolution of the North American continent and how dynamic topography may have influenced this history. It will specifically focus on the implications of our results for 1) the potential significance of more substantial post-100 Ma burial across the central U.S. than previously recognized, and 2) the Paleozoic-Mesozoic burial, erosion, and vertical motion history across the North American interior and its possible dynamic cause.