Geomorphic Development of Marine Terraces at Jeongdongjin-Daejin area on the East Coast, Central Part of Korean Peninsula Soon-Ock Yoon*, Sang-Ill Hwang** and Hak-Kyun Ban*** Abstract : In this paper we identify that there are High Higher surfaces(hh-surface) around Jeongdongjin and Daejin area where Higher surfaces(h-surface) of marine terrace are formed on a large scale. On the basis of an altitude of the ancient shoreline of the marine terraces, geomorphic surfaces can be classified into HH I (140m a.s.l), HH II (110m a.s.l), H I (90m a.s.l), H II (70m a.s.l), M (40m a.s.l), L I (25m a.s.l) and L II (10m a.s.l). Besides, we identify that the lowest surfaces(5~6m a.s.l) are found extensively in the research area which are assumed to be formed in the Holocene. Considering that the formation mechanism of the marine terraces in the research area is similar to that of the marine terraces at both Gampo area in the south east coastal region of Korea and the thalassostatic terraces of Osip River in Samchuk in a short distance from the research area, we can assume that the HH-surfaces in both areas were formed in the same period. Based on the fact that L I- surface was formed on the Last Interglacial Stage of MIS 5, we can infer that M- was formed in MIS 7, H I- in MIS 9, H II- in MIS 11, HH I- in MIS 13 and HH II- in MIS 15. The reason for that H-surfaces, similar to those at Gampo area, to remain on a large scale is that the Holsteinian Interglacial continued for a long period of time and at that time there was a large wave-cut platform in the vicinity of the shoreline. Key Words : Jeongdongjin-Daejin area, marine terrace, High Higher surfaces, Higher surfaces, the Holsteinian Interglacial stage (Associate Professor, Dept, of Geography and Research Institute for Basic Sciences, KyungHee University), soyoon@khu.ac.kr (Assistant Professor, Department of Geography, Kyungpook National University) (Teacher, Gwangju High School, Gyeonggi-do) 156
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