High-Resolution Bathymetric Mapping of Iskenderun Bay, Türkiye: Insights into Morphological and Tectonic Features

Abstract

Iskenderun Bay, situated at the tectonically dynamic triple junction of the African, Arabian, and Anatolian plates in the northeastern Mediterranean, exhibits complex deformation driven by ongoing plate interactions. The region's structural complexity arises from the westward convergence of the African-Anatolian plates and the collision of the Arabian-Anatolian blocks. Post-Middle Miocene escape tectonics along the Dead Sea Fault Zone (DSFZ) generated the North Anatolian and East Anatolian Fault Zones (EAFZ). The EAFZ segment southeast of the Maraş Triple Junction remains enigmatic due to its subdued surface expression and sparse geophysical constraints. Here, we present the first high-resolution digital bathymetric model (DBM) of Iskenderun Bay, derived from multibeam bathymetric surveys. Our dataset reveals previously unresolved seafloor morpho-structures, including fault-controlled slopes and submarine ridges, providing critical evidence for the submerged continuation of the EAFZ. The bay's predominantly flat morphology contrasts with localized deformation along its eastern and southwestern margins, reflecting active tectonic partitioning. These findings gain urgency following the 6 February 2023, Mw 7.8 and Mw 7.6 earthquakes, underscoring the seismic hazard posed by unresolved fault geometries in this densely populated region.