This project will investigate the seismicity associated with the major tectonic regimes of Africa using a combination of earthquake seismology, satellite geodesy, and structural geology. The range of tectonic environments, styles of deformation, and geological settings in which active faulting and seismicity take place provide an ideal opportunity to investigate the controls that rheology of both the fault zone and the bulk lithosphere play on the evolution and interaction of fault systems, and their expression in seismic activity.
Africa hosts a wide variety of deformational regimes, from compression along the margins of North Africa, focussed extension extending from the oceanic rifts of the Red Sea and the Gulf of Aden, through the Afar, to the continental rifts of East Africa, diffuse extension and distributed rifting in southern Africa, and intraplate deformation across the Congo basin and the Okavango. All of these regimes behave seismically. This wide range of tectonic settings spanning the entire continent, presents an opportunity to investigate how variations in the geological context (controlling both the rheology of individual fault zones, and the larger-scale bulk rheology of the lithosphere) influence the seismicity, and the style and evolution of faulting.
This project will initially focus on investigating the seismicity of East Africa, along the rift system, using a combination of earthquake seismology and satellite geodesy. East Africa shows a well-established first order increase in lithospheric strength from north to south, accompanied by a concomitant increase in the scaling the tectonic structures. With increasing data coverage (at both global and regional scales, seismologically, along with the advert of short-repeat-time satellite coverage from the ESA’s Sentinel satellites), the project will aim to improve the resolution at which these variations are observed, furthering our understanding of the controls on this process. The project will then use this revised understanding to address the question of the evolution and interaction of the fault systems along the rift system, drawing on both satellite data and structural geology.
This initial project will train the successful candidate in research, providing a range of technical skills that can then be applied to a whole set of problems relating to the tectonics and seismicity of Africa, based on the students interests. Avenues exist in East Africa to look at the longer-term dynamics of the faulting process, either on decadal timescales using satellite geodesy, or on Quaternary timescales through the evolution and interaction of fault networks. As well as widespread seismicity, Eastern Africa also hosts a fascinating interplay between tectonic and magmatic extensional processes, and presents an opportunity to study the interaction and feedback between these two modes of extension – both at the level of individual events, and in terms of the longer-term tectonic evolution of the rift system.
Alternatively, the project may evolve to investigate comparisons between the seismicity and faulting associated with extensional in East Africa, and the compressional tectonics of North Africa, with a potentially-lucrative avenue looking at the influence that the tectonic deformation in these two settings has on the longer-term landscale evolution.
The successful candidate will be part of the Tectonics Research group of the Institute of Geophysics and Tectonics (School of Earth and Environment) of the University of Leeds. The Tectonics Research group is a large and dynamic research group including Seismology, Structural Geology, Geomorphology, Quaternary Research and Remote Sensing. The PhD student will benefit from training from the Leeds-York-Hull Doctoral Training Partnership as well as from training at the university, and will be attending national and international conferences and workshops. Possibilities for participation in fieldwork might arise in other projects at the Institute for Geophysics and Tectonics.
Funding for this project is available through open competition in the Leeds/York PANORAMA DTP (View Website), and open to applications from the UK and the wider European Union.
A. Copley et al., (2012). Constraints on fault and lithosphere rheology from the coseismic slip and postseismic afterslip of the 2006 Mw 7.0 Mozambique earthquake, Journal of Geophysical Research, v117, doi: 10.1029/2011JB008580.
T. J. Craig et al., (2011). Earthquake distribution patterns in Africa: Their relationship to variations in lithospheric and geological structure, and their rheological implications, Geophysical Journal International, v185, p403-434.
C.J. Ebinger et al., (2019). Kinematics of Active Deformation in the Malawi Rift and Rungwe Volcanic Province, Africa, Geochemistry, Geophysics, Geosystems, doi:10.1029/2019GC008354.
A. Lavayssiere et al., (2019). Depth extent and kinematics of faulting in the southern Tanganyika Rift, Africa, Tectonics, v38, pp842-862.
T. J. Wright et al., (2012). Geophysical constraints on the dynamics of spreading centres from rifting episodes on land, Nature Geoscience, v5 doi:10.1038/NGEO1428.
How good is research at University of Leeds in Earth Systems and Environmental Sciences?
FTE Category A staff submitted: 79.20
Research output data provided by the Research Excellence Framework (REF)
Click here to see the results for all UK universities