Tsunami hazard assessment in the Makran subduction zone

TL;DR

This study models probabilistic tsunamis in the Makran subduction zone considering slip heterogeneity and non-planar geometry, identifying vulnerable coastal areas with potential run-up heights up to 16 meters.

Contribution

It introduces a novel probabilistic tsunami hazard assessment using synthetic slip models for the Makran subduction zone with non-planar geometry.

Findings

Maximum run-up of 16 meters along Iran and Pakistan coasts.

Vulnerable areas identified between Jask and Ormara, and Muscat and Sur.

Slip heterogeneity significantly influences tsunami impact in the most affected regions.

Abstract

The lack of offshore seismic data caused uncertainties associated to understating the behavior of future tsunamigenic earthquakes in the Makran Subduction Zone (MSZ). Future tsunamigenic events in the MSZ may trigger significant near-field tsunamis. Run-up heights in the near-field are controlled by the heterogeneity of slip over the rupture area. Considering a non-planar geometry for the Makran subduction zone, a range of random k^{-2} slip models were generated to hypothesize rupturing on the fault zone. We model tsunamis numerically and assess probabilistic tsunami hazard in the near-field for all synthetic scenarios. The main affected areas by tsunami waves are the area between Jask and Ormara along the shorelines of Iran and Pakistan and the area between Muscat and Sur along the Oman coastline. The maximum peak-run-up along the shores of Iran and Pakistan is about 16 m and about 12 m for the Oman shoreline. The slip distributions control the run-up along the Makran coastlines. The dependency of run-up to the heterogeneity of slip is higher in the most impacted areas. Those areas are more vulnerable to tsunami hazard than other areas.