Abstract

The East African Rift System offers a unique opportunity to study the development of continental rifts, from amagmatic basins in the south to nascent seafloor spreading in the north. The canonical model is that continental extension initially forms a network of short fault segments, which gradually grow and link to form long border faults along pre-existing weak zones. As stretching continues, the lithosphere–asthenosphere boundary rises, and the volume of decompression melting increases. Magmatism and faulting become localised along magmatic segments within the basin. Ultimately, extension is dominated by dyke intrusions into very thin crust, resembling the processes of seafloor spreading. However, in reality, the continental lithosphere is highly heterogeneous, producing a diversity of tectonic and magmatic processes that do not always fit this simple story. In this talk, I will demonstrate how satellite observations are providing a fresh perspective on tectonic and magmatic processes at a continental scale, allowing us to target fieldwork to understand the active processes by which continental rifts form and the hazards they pose.  I will show how using high resolution Digital Elevation Models has allowed us to map active fault scarps across the amagmatic Malawi Rift and what InSAR observations have revealed about magmatic activity within the mature continental rifts of Kenya and Ethiopia. Finally, I will discuss the crisis response and ongoing scientific investigation into the 2024-2025 Fentale-Dofen seismic-tectonic crisis, which was caused by the intrusion of a 50 km long dyke and triggered the evacuation of 75,000 people.