Review in Seismotectonic setting of Gulf of Aqaba with respect to the 27th June 2015 and 16th May 2016 Aqaba earthquake swarms
Abdelaziz Khairy, National Research Institute of Astronomy and Geophysics
Shaimaa Mostafa, Zagazig University
In this paper, we review recent seismicity and seismotectonic setting of Gulf of Aqaba, based on two recently significant swarms occurred on 27th June 2015 and 16th May 2016. Seismologically, the Gulf of Aqaba is one of the most active places around Egypt, where several earthquake swarms have occurred through ancient and modern times. In the last century, four earthquake swarms of 1983, 1990, 1993 and 1995 have been instrumentally recorded. Recently, on 27th June 2015 a swarm of 96 earthquakes with local magnitudes ranging from 0.7 to 5.2 were recorded by the Egyptian National Seismological Network. On 16th May 2016 another swarm started and continued for several consecutive days, and approximately 95 events with local magnitudes ranging from 1.6 to 5.5 was instrumentally recorded in the gulf south of 27th June 2015 swarm. The complete waveform and polarity data set of both two swarms recorded by the broadband and short period stations of the Egyptian National Seismological Network were essentially analysed to determine type and geometry of faults and to update our knowledge in stress field and tectonic setting of the Gulf of Aqaba. Through the obtained results, we can divide the Gulf of Aqaba tectonically into several segments each segment having different seismic characteristics than the other. The scientific truth that gathers all the gulf segments is that the fault segments are of a kind left lateral strike slip with minor normal component in some segments and right lateral strike slip with minor reverse component in the other