Source-to-Sink (S2S) of the Korean Shelf Mud deposits since the 6 ka

Based on analyses of high-resolution seismic profiles and sedimentary data, we investigated the Holocene evolution and sediment budget of three shelf mud deposits distributed along the Korean Peninsula: the Southeastern Yellow Sea Mud (SEYSM), Central South Sea Mud (CSSM), and Korea Strait Shelf Mud (KSSM). These mud accumulations, which began forming around 6 ka, are integral components of the fine-grained source-to-sink system in the marginal seas of Korea. Although previous studies have examined their distribution and facies characteristics, quantitative sediment budget assessment among these deposits has remained insufficient. This study elucidates the interrelationships between the SEYSM, CSSM, and KSSM, along with the role of estuarine filtration and coastal hydrodynamics in modulating sediment transport. An estimated 32.5–43.8 × 10⁶ tons of suspended material are annually supplied to the region through multiple sediment sources. Seasonal variations in oceanic fronts and longshore currents control sediment dispersal along the Korean coast, resulting in distinct deposition patterns. The estimated annual accumulation rates are 9.0–13.2 × 10⁶ ton/year for the upper SEYSM, 5.3–8.1 × 10⁶ ton/year for the CSSM, and 4.6–6.4 × 10⁶ ton/year for the KSSM, corresponding to approximately 28–30%, 17–18%, and 14–15% of the total sediment input, respectively. Additionally, about 17–25% of fine-grained sediments are exported toward the Ulleung Basin. These sediment budget estimations provide new insights into sediment transport pathways, source-to-sink fluxes, and depositional connectivity among the Korean shelf mud systems, contributing to a refined understanding of Holocene sedimentary processes on the continental shelf.