Abstract
An understanding of the fundamental processes by which continental rifts form and develop is necessary to fully understand plate tectonics and the associated earthquake and volcano hazards. Fault slip, magma chamber inflation and magma intrusion produce characteristic patterns of surface deformation which can be the key to characterising the active tectonic and magmatic processes. The ISMER project uses archived and scheduled satellite radar images to analyse surface displacements along the length of the East African Rift over the past 15 years. Where available we use seismological observations from global catalogues and local networks to target our observations, and perform systematic surveys over key areas to identify aseismic processes. In this article, we summarise published findings on the Kenyan (1997–2008) and Main Ethiopian Rifts and the 2009 Malawi earthquakes and describe new results from the Western Branch, the Kenyan Rift (2008–2010) and a series of seismic swarms. Due to InSAR studies such as these, the number of volcanoes known to be active in East Africa has gone from 3 (Nyiragongo, Nyamuragira and Oldonyo Lengai) to >14 with implications for volcanic hazard and geothermal potential.
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Acknowledgments
This project was supported by the ESA Changing Earth Science Network, COMET+ at the University of Oxford and a lectureship at the University of Bristol. ER is supported by a NERC studentship to the University of Bristol; MM was supported by a NERC undergraduate summer placement. With thanks to Diego Fernandez, Steffen Dransfeld, Roberto Sabia and many other people at ESA who have helped in so many ways. We thank the anonymous reviewer for helpful comments. Much of the work summarised here has been published in other articles and I thank my co-authors: Ian Bastow, Derek Keir, Elias Lewi, Edwin Nissen, Tim Craig, James Jackson and David Robinson.
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Biggs, J., Robertson, E., Mace, M. (2013). ISMER—Active Magmatic Processes in the East African Rift: A Satellite Radar Perspective. In: Remote Sensing Advances for Earth System Science. SpringerBriefs in Earth System Sciences. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-32521-2_9
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DOI: https://doi.org/10.1007/978-3-642-32521-2_9
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