A new kinematic approach for the Danakil block using a Digital Elevation Model representation

Abstract Data from the literature are integrated in a regional Digital Elevation Model (DEM) in order to analyse the motion of the Danakil block with regard to the Arabian and Somalian plates. The application of the poles and angles of rotation taken from the literature, induces a superposition of the Danakil block on the Arabian plate, and the formation of a gap in the Afar region. The determination of new poles of rotation using a best-fitting procedure allows one to avoid these drawbacks. In all cases, calculations are carried out keeping the Nubian plate stationary. The present approach shows that the Danakil block is an independent entity and is not related to the Nubian and Arabian plates. Between the Oligocene and the Miocene, it has been submitted to a N20°E sinistral strike-slip motion anterior to the rotation itself that was started in the middle Miocene. This rotation is directed by a mechanical couple due to the combination of the Red Sea and North Afar extensions.

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