CRUSTAL THICKNESS AND VP/VS VARIATIONS IN JORDAN INFERRED FROM TELESEISMIC P-RECEIVER FUNCTIONS

Crustal structure of Jordan was previously studied using deep sounding refraction profiles which led to deducing average crustal structure and Vp/Vs ratios. Other attempts employed different geophysical methods were mainly focused on crustal structure along Dead-Sea Transform Fault which is the main tectonic element in this area. The present work elucidates detailed crustal structure of Jordan using P-wave receiver functions technique. The RF method is applied for the first time to teleseismic earthquakes data from 15 broadband permanent stations that are covering the whole of Jordan and along the Eastern side of Northern part of Arabian plate boundary. The results indicate varying Moho depths beneath selected stations near the main fault and to the east of it, and reveal a thick crust under northern stations (about 35 +/- 1 km) with Vp/Vs ratio of about 1.8. In the northeastern part of Jordan, three stations show deeper Moho depths with varying Vp/Vs ratios ranging from 1.76-1.79, they are situated in the area of basaltic extrusions that can be interpreted as more mafic crustal content in average. The thinnest crust of similar to 30.5 km occurs in the southern Dead-Sea basin along the Transform Fault and near the Gulf of Aqaba (similar to 30.4 km) with Vp/Vs ratios ranging from 1.83 to 1.79, respectively. The crust in Jordan is thickening toward north and northeast. Finally, a 3D topographic map of the Moho discontinuity was constructed.