Development of a regional probabilistic seismic hazard model for Central Asia

Abstract. Central Asia is an area characterized by complex tectonic and active deformation, largely due to the relative convergent motion between India–Arabia and Eurasia. The resulting compressional tectonic regime is responsible for the development of significant seismic activity, which, along with other natural hazards such as mass movements and river flooding, contributes to increased risk to local populations. Although several studies have been conducted on individual perils at the local and national levels, the last published regional model for the whole of Central Asia, developed under the EMCA (Earthquake Model Central Asia) project, is almost 10 years old. With the goal of developing a new comprehensive multi-risk model that is uniform and consistent across the five Central Asian countries of Kazakhstan, the Kyrgyz Republic, Tajikistan, Turkmenistan, and Uzbekistan, the European Union, in collaboration with the World Bank and the Global Facility for Disaster Reduction and Recovery (GFDRR), funded the regional programme SFRARR (Strengthening Financial Resilience and Accelerating Risk Reduction in Central Asia). The activity was led by a consortium of scientists from international research institutions, from both the public and the private sectors, with contributions from experts of the local scientific community. This study presents the main results of a probabilistic seismic hazard analysis (PSHA) conducted as part of the SFRARR programme to develop the new risk model for Central Asia. The proposed PSHA model was developed using state-of-the-art methods and calibrated based on the most up-to-date information available for the region, including a novel homogenized earthquake catalogue compiled from global and local sources and a database of active faults with associated slip rate information.