Crustal deformation and volcanic plumbing during the magmatic pulse at the final stages of continental breakup

Derek Keir, James Hammond
2014
Crustal deformation and volcanic plumbing during the magmatic pulse at the final stages of continental breakup
This is a Full Scientific Report resulting from NERC Geophysical Equipment Facility Loan 956, principal investigator Dr Derek Keir.

Abstract

SEIS‐UK provided a loan of 13 broadband seismic systems (10 x CMGESP and 3 x 6TDs), for deployment in a network of approximately 150km x 200km in the northern portions of the Afar depression. Instruments were kept in the Afar depression from February 2012 to January 2013. These systems recorded continuously at 50Hz with relatively minor data losses due to equipment problems. Background seismicity has been analysed in northernmost Afar for the period February 2012 to January 2013. Results show both the border faults and axial fauls in the Danakil depression are active and the seismogenic thickness is very shallow at around 6 km. Teleseismic data is being used to constrain lithosphere and asthenosphere structure beneath Afar, the Red Sea, Gulf of Aden and Yemen using surface‐wave tomography. Results show segmented low velocity zones beneath the ocean ridges suggested segmented upwelling and partial melting of asthenosphere.