High-resolution seismic study of modern fine-grained deposits: Inner shelf off the southeastern coast of Korea

The geometry and internal structures of modern sediments on the inner shelf off the southeastern coast of Korea were investigated by means of analysing high-frequency (3.5 kHz) seismic records. The records reveal a wedge-shaped sediment body, tapering off toward the sea. On the basis of reflection patterns, the sediments can be classified into two units; “foreset” (prodelta) unit and “bottomset” unit, consisting of sandy muds and clays, respectively. The lateral transition from foreset to bottomset deposits suggests a prograding delta system of the Nakdong River since the late Holocene.