Earthquake catalog improvements and their seismic hazard impacts for the Arabian Peninsula

Abstract

The Reviewed Event Bulletin (REB) issued through the International Data Centre (IDC) using the International Monitoring System (IMS) network of the Preparatory Commission for the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) is a seismo-acoustic bulletin distributed to the Member States of the CTBTO for the purpose of verifying the Treaty. The REB is partially available within a few days on the public site of the International Seismological Center (ISC), where the REB events are labeled ‘IDC’. This study focuses on the seismicity of the Arabian Peninsula and its adjacent regions, but the conclusions would be similar for regions that include good quality seismic stations of the IMS auxiliary seismic network, which has no weight in the current Event Definition Criteria (EDC). It is indicated that the consideration of the confidence ellipse factors (semi-major a-axis, semi-minor b-axis, and the epicentral area (A) as alternative EDC would significantly improve the completeness of the REB for the Arabian Peninsula, which consequently enhance the quality of the ISC bulletin.The Arabian Peninsula has been chosen as a study region not only because it is surrounded by the IMS auxiliary seismic stations but also due to its increasing population, rapid urbanization, and strong economic growth in recent years. It has attracted many mega-projects (e.g., Multinational NEUM in Saudi Arabia, Expo 2020 in Dubai, the Special Economic Zone at Duqm in Oman, and the World Cup 2022 in Qatar). The earthquake hazards impact for the big cities in Saudi Arabia, such as Dammam in the east, and Jeddah, Tabuk, and Jizan in the west and the nearby cities are reviewed. The completeness catalog of the revised earthquakes may serve to improve the calculation of earthquake hazards threatening big cities in and around Saudi Arabia.