For most continental areas, the mechanisms leading to mantle fabrics responsible for the observed anisotropy remain ambiguous, partially due to the lack of sufficient spatial coverage of reliable seismological observations. Here we report the first joint analysis of shear-wave splitting measurements obtained at stations on the Arabian and Nubian Plates adjacent to the Red Sea. More than 1100 pairs of high-quality splitting parameters show dominantly N-S fast orientations at all 47 stations and larger-than-normal splitting times beneath the Afro-Arabian Dome (AAD). The uniformly N-S fast orientations and large splitting times up to 1.5 s are inconsistent with significant contributions from the lithosphere, which is about 50–80 km thick beneath the AAD and even thinner beneath the Red Sea. The results can best be explained by simple shear between the lithosphere and the asthenosphere associated with northward subduction of the African/Arabian Plates over the past 150 Ma.
A. A. Elsheikh et al., "Seismic Anisotropy and Subduction-Induced Mantle Fabrics beneath the Arabian and Nubian Plates Adjacent to the Red Sea," Geophysical Research Letters, vol. 41, no. 7, pp. 2376-2381, American Geophysical Union, Apr 2014.
The definitive version is available at https://doi.org/10.1002/2014GL059536
Geosciences and Geological and Petroleum Engineering
Center for High Performance Computing Research
Keywords and Phrases
Anisotropy; Egypt; Mantle Flow; Red Sea; Saudi Arabia; Seismic Anisotropy; Shear Wave Splitting; Shear Waves; Asthenosphere; Joint; Mantle Plume; S-Wave; Seismic Anisotropy; Subduction; Egypt; Red Sea [(GVR) Egypt]; Saudi Arabia
International Standard Serial Number (ISSN)
Article - Journal
© 2014 American Geophysical Union, All rights reserved.
01 Apr 2014