Sedimentary Environments of Hampyong Bay, the Southwestern Coast of Korea

For depositional environments of Hampyong Bay, which is a typical tide-inlet bay in the southwestern coast of Korea, a study on the suspended matters and physical properties of seawater, accumulation rate and distribution of surface sediments, and morphology were carried out. Temperature and salinity of seawater, and the concentrations of suspended matters were relatively high in hay-mouth than bay-head. Tidal currents are persistent with SE∼NW directions in the bay-mouth and the bay-head. Accordingly, the tidal circulation is very simple through the main tidal channel. Velocity of the tidal currents is relatively strong in the bay-mouth than the bay-head. The surface sediments of Hampyong Bay show several distribution patterns, widely ranging pebble to clay in grain size. The coarser sediments are widely distributed on the bay-mouth subtidal zone and bay-head intertidal zone, whereas the finner sediments dominate on the intertidal zone of both sides of the main tidal channel. Annual accumulation rates on the tidal flats were measured -42.6 ㎜/yr in mud flat and -0.1 ㎜/yr in mixed flat, respectively, indicating erosion-dominated environment. In the mud flat, the finer sediments are eroded in summer, and deposited in winter. In the mixed flat, however, this trends are opposite to those in the mud flat.at