DISCIPLINAL COUPLING OF A HIGH-RESOLUTION OCEAN MODEL AND MARINE GEOLOGY FOR A MILLENNIUM-SCALE MORPHODYNAMIC ANALYSIS IN THE EASTERN SETO INLAND SEA

Abstract

 In order to quantify the formation mechanism of seafloor topography on a timescale of millennia in the eastern Seto Inland Sea, the Regional Ocean Modeling System (ROMS) was used to evaluate hydraulic quantities and diagnose suspended sediment transport, coupled with the marine geological discipline. Overall morphodynamics was well captured by the diagnostic model, in which the intensity of bottom shear stress associated with prevailing tidal currents and the divergence of bottom residual currents explain the formations of caldrons and sandbanks. Nevertheless, inconsistency between the background hydrodynamics and the resultant topographies were found in multiple places around tidal straits. We showed that marine geological data was quite useful to fulfil a comprehensive description of, e.g., unexplained zonal differences of sandbank formation relative to Akashi Strait through the considerations of coastal transgression.