빙기에 동해안에서 형성된 유사 해안단구 지형

Abstract

While many landforms in Korea have erroneously been recognized as marine terraces based on their shape and sedimentary characteristics, optically stimulated luminescence (OSL) dating indicates that these formations originated during the glacial stage. This result suggests that these landforms are pseudo-marine terraces because they were shaped by terrigenous processes rather than marine processes. Analyzed at 12 sites, these pseudo-marine terraces were classified into three different types: 1) coastal landforms by reworking of marine terrace sediments, 2) coastal alluvial fans, and 3) coastal fluvial terraces. The first type is coastal landforms where marine terrace sediments were originally deposited during a previous interglacial stage, and dissected, transported, and redeposited during the following glacial stage. The second type is alluvial fans formed by material supplied from slopes through small streams or landslides during the glacial stage. The third type includes fluvial terraces, where floodplains were formed in valley bottoms during the glacial stage and later preserved along the coast due to subsequent incision and dissection.