Special Seminar, Sarah Stamps: Advances in Techtonics and Hazards Using Geodesy
Advancing our understanding of tectonic processes and their associated geohazards is important for the safety of our society. In this presentation, I will address extension of the African continent along the East African Rift and volcanic hazards in Tanzania that are linked with the divergence of Africa. Previous studies have constrained the kinematics of Africa and surroundings using GNSS/GPS geodesy and suggest extension is accommodated in narrow zones bounding rigid blocks. However, in this work I will present a GNSS/GPS velocity solution comprised of 12 years of observations that constrains a new kinematic model of the region. The new model redefines the kinematics of the East Africa Rift with a broad zone of diffuse deformation identified as stretching from Africa’s east coast to parts of Madagascar. Madagascar is also shown to be slowly breaking up at 1.5 mm/yr. Extension rates in Tanzania are 3.8 mm/yr across the magma-rich Natron Rift, which hosts the Earth’s only active carbonatite volcano, Ol Doinyo Lengai. I will also present advances in volcanic hazards assessment based on data from the TZVOLCANO GNSS/GPS and seismic network, as well as additional constraints from InSAR observations. Investigations of the magma plumbing system feeding Ol Doinyo Lengai using high latency GNSS/GPS geodesy, InSAR, and inverse modeling suggest a complex multi-tiered reservoir system. Additionally, I will highlight our recent work in analyzing low latency GNSS/GPS data with unsupervised machine learning to detect anomalous surface motions towards rapid volcanic hazards assessment. Finally, I will conclude the presentation with an overview of other active and developing scientific projects as well as some of my efforts to improve inclusion and diversity in the geosciences.
*light refreshments will follow