The key role of conjugate fault system in importing earthquakes into the eastern flank of the Red Sea

Journal Article

2021

Published in: https://link.springer.com/content/pdf/10.1186/s40623-021-01513-1.pdf?pdf=button

This study aims to synthesize seismic observations with gravity and magnetic data and to suggest a new scenario
on the development of the Harrat Lunayyir (HL) tectonic system on the eastern Red Sea coastline, Saudi Arabia.
Gravity and aeromagnetic anomalies distinctly mapped the NE and NW trends, while the InSAR data depict a small
NW–SE graben and an NW–SE dyke. High-resolution relocations, which are well-consistent with the focal mechanism solutions for events with magnitudes greater than 3.0, admit two distinctly fault styles of diferent orientations. Thus, leading to the NE and NW fault planes’ reactivation related to the Precambrian basement faults and the Red Sea rift system, respectively. The spatiotemporal distributions of epicenters and focal mechanism solutions suggest a new seismic deformation scenario of the 2009 earthquake seismic activity. The low static frictions of 0.2–0.35 obtained from the stress inversion indicates reactivation of preexisting faults in the respective seismogenic zones. The obtained results give rise to a swarm-like sequence of tectonic implications, two activated fault styles diferently oriented, and an NE conjugate fault system inherited in the region, which plays a vital role in transferring the ambient stress regime into the Red Sea’s eastern fank.

• Publication Work Type: Research
• Publisher Name: Springer Berlin Heidelberg
• Volume Number: 73
• Magazine \ Newspaper: Earth, Planets and Space
• Pages: 1-19