Active Rifting in the East African Rift System and Challenges in Disaster Risk Management
The roughly 3000 km long East Africa Rift system (EARS) is one of the striking features of the African continent that captures all stages of rift development from the most juvenile to nascent seafloor spreading in Okavango delta and Afar depression, respectively. It provides a natural laboratory for studying a fundamental, and yet enigmatic, component of plate tectonics. A mechanism for rupturing thick, cold, continental lithosphere is not readily apparent in conventional models of mechanical stretching. Magma production weakens the plate and serve to localize strain, thus better facilitating rifting. Studies of seismicity and volcanism provide insights into this problem and a variety of geophysical, geochemical and geological studies can be used to better understand the role of the crust and mantle in continental breakup. However, observational data have limitations in the global south both in quality and density which poses constraints for detailed investigation and understanding of the rift process.

Permanent seismic station distribution is sparse in the continent but some focused and episodic studies have been conducted using temporary broad seismic networks in collaboration with overseas researchers. Earthquakes of magnitude 7.0 and above are observed in EARS from instrumentally recorded seismicity (the 1910 Rukwa earthquake in Tanzania, the 1990 earthquake in South Sudan and the 2006 Machase earthquake in Mozambique) which is a wakeup call for the fast growing construction industry in the region. It is inferred that the EARS is more active than we think, from recently recorded seismicity, which requires collaborative efforts to enhance studies in the region both to enhance basic science research and disaster risk management in the continent.
Date: 16 June 2023, 12:00
Venue: Department of Earth Sciences, South Parks Road OX1 3AN
Venue Details: Lecture Theatre
Speaker: Prof Atalay Ayele (University of Addis Ababa)
Organising department: Department of Earth Sciences
Part of: Earth Sciences departmental seminars
Booking required?: Not required
Booking url: https://www.earth.ox.ac.uk/events/week-8-research-seminar/
Audience: Public
Editor: Maria Petrunova