GPS evidence for northward motion of the Sinai Block: Implications for E. Mediterranean tectonics

TLDR: In this article, an elastic block model constrained by the GPS results that is consistent with the regional tectonics and allows us to estimate slip rates for Sinai bounding faults, including the Gulf of Aqaba-southern Dead Sea fault system, is presented.

About: This article is published in Earth and Planetary Science Letters.The article was published on 2005-09-30 and is currently open access. It has received 119 citations till now. The article focuses on the topics: Strike-slip tectonics.

Figures

Fig. 3. Elastic block model for the Sinai area showing GPS residual velocities (given in Table 1) for the model described in the text. Faults are vertical and assigned locking depths of 15 km except for the Gulf of Aqaba/Dead Sea fault system that has a locking depth of 13 km, and the western Cyprus Arc that has a 308 dip down to the NE. Residuals are well within the uncertainties for the velocity determinations. Numbers show fault strike slip and fault-normal slip rates and 1-sigma formal uncertainties (fault normal component in brackets; negative for left lateral and extension). Slip rates are averages along each segment. Light modeled faults indicate segments with fault-normal shortening, and dark extension. Inset shows a plot of the local Chi*2 computed from sites close to the fault (shaded error ellipses indicate sites used to estimate fault locking depth) and estimated fault strike slip rate as a function of the locking depth for the Dead Sea fault. The best fit is for a 13 km locking depth and a strike slip rate of 4.3 mm/yr.

Fig. 1. Topographic (SRTM30) and tectonic map of the Sinai and surrounding region. Dots show seismicity (NEIC), focal mechanisms are from Harvard CMT. Inset shows location of study area within the context of the eastern Mediterranean. DSF=Dead Sea fault, Gulf of Iske.=Gulf of Iskenderum.

Table 2 Euler vectors relative to Eurasia and 1-sigma uncertainties estimated from this study

Fig. 2. Simplified tectonic map of the Sinai and surrounding regions show Lines with tick-marks are normal faults, ticks on downthrown block, doubl are given in Table 1.

Table 1 GPS velocities in an Africa (Nubia)-fixed reference frame and 1-sigma uncertainties for sites shown in Fig. 2