Understanding the Changes in the Post-Glacial Depositional Environments through High-resolution Geochemical Proxies in the Central Yellow Sea

Sediment cores (A10 and I06) were analyzed using a high-resolution X-ray fluorescence (XRF) core scanner to understand changes in paleo-sedimentary environments of the study area. Age dating reflects environmental changes from interglacial marine isotope stage 3 (MIS 3) through the last glacial maximum (LGM; MIS 2) to the Holocene. Three layers were identified in the seismic profiles as follows: unit 1 (thickness = ca. 5 m) in a homogeneous sedimentary phase; unit 2 formed by erosion; unit 3, which is parallel and continuous. XRF elemental proxy data indicate anomalous distributions of Ca/Fe, Ca/K, and Fe/Ti caused by organic substances that appear at several depths in the A10 core. Results show that the seafloor was exposed to air during the LGM. The I06 core shows characteristic anomalies at depths of 0.8, 1.5, and 2.5 m, which were caused by sediments supplied from surrounding rivers.