Linkage between Arabian subducting slab geometry, major fault systems, and seismicity in the Makran subduction zone

Seismicity in subduction zones, both interplate and intraslab is primarily influenced by fault dynamics in the accretionary prism, the seismogenic interface separating the downgoing oceanic lithosphere from the overriding plate, and slab geometry. However, their combined influence on seismic hazards remains inadequately constrained, particulary in the Makran subduction zone. In this study, we develop a novel Entropy-Analytic Hierarchy Process (AHP) hybrid seismic hazard model by integrating seismic catalogs, slab geometry, major thrust and strike-slip fault traces, gravity anomalies, and topography to examine relationships between the Arabian subducting slab, major fault dynamics, and seismic hazards. The Arabian slab exhibits pronounced spatial variations in thickness, depth, dip, and strike, which modulate stress distribution and regional seismicity. The Entropy-AHP hybrid model classifies seismic hazard into high, moderate, and low levels. The results reveal that high seismic hazard levels are linked to steep slab dips, associated with slab pull and bending stresses, and shallow slab depths, which promote brittle failure in cooler, hydrated slabs. Furthermore, high seismic hazard levels strongly correlate with proximity to the subduction interface, major thrust faults in the accretionary prism, the right-lateral Minab Fault (MF) in the west, and the left-lateral Ornach-Nal Fault (ONF) in the east, reflecting the influence of tectonic coupling, stress accumulation, and release. Additionally, moderate positive correlations between high seismic hazard levels and gravity anomalies suggest that variations in accretionary prism density also contribute to hazard distribution. These findings enhance our understanding of Makran subduction dynamics and seismic hazard assessment, with direct implications for tsunami preparedness and infrastructure resilience planning.