• The Korean Journal of Quaternary Research
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• v.20 no.2
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• pp.51-57
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• 2006

Terrace stratigraphy of the southeastern coastal areas of Korea is reappraised on the basis of terrace mapping and geochronology. Coastal terraces are divided into uHT ($90{\sim}130\;m$), HT ($63{\sim}86m$), MT ($36{\sim}55\;m$), and LT ($8{\sim}25\;m$) according to altitude. Among these, the Lower Terrace I is interpreted to have formed during MIS 5e based on Tephras Aso-4 (MIS 5c), Ata(MIS 5d or 5e) and OSL data. The age of Lower Terrace II is thought to be MIS 5a based on tephras and OSL data. The uplift rate in the SE part of Korea during the formation of the Lower Terrace (i.e. the MIS 5) ranges from 0.08 to 0.25 mm/yr and averages as 0.15 mm/yr. Such value is quite small in comparison to that of Japan, Taiwan or many other tectonically active areas in the world.

• The Korean Journal of Quaternary Research
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• v.19 no.2
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• pp.18-20
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• 2005

• Journal of The Geomorphological Association of Korea
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• v.26 no.4
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• pp.81-96
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• 2019

The Yeongdeok 53m marine terrace (Y₅₃mT), Y₄₃mT, Y₃₃mT, Y₂₄mT, Y₁₉mT and Y₁₁mT distributed along the Yeongdeok coast, southeastern Korean Peninsula are well compared with the thalassostatic terraces of the high terrace 1 (ℓHT₁ ; 51m of the relative heights from the river floor), high terrace 2 (ℓHT₂ ; 43m), middle terrace 1 (ℓMT₁ ; 32m), middle terrace 2 (ℓMT₂ ; 25m), lower terrace 1 (ℓLT₁ ; 18m) and lower terrace 2 (ℓLT₂ ; 10m) respectively, developed along the lower reaches of the Chucksan-cheon and Obo-cheon rivers, judging from the comparison of paleosols (red soils) between the above marine and thalassostatic terraces. Using the Y₁₉mT of the MIS 5e as the key surface, we propose that the terraces of the Y₅₃mT and ℓHT₁, Y₄₃mT and ℓHT₂, T₃₃mT and ℓMT₁, Y₂₄mT and ℓMT₂, Y₁₉mT and ℓLT₁, and Y₁₁mT and ℓLT₂ have been formed at the MIS 11, 9, 7e and 7a (or 7a), 5e and 5a respectively. The red soils have been developed at the Y₁₉mT and ℓLT₁ and above them, but not on the Y₁₁mT and ℓLT₂ surfaces.

• The Korean Journal of Quaternary Research
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• v.17 no.2
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• pp.15-15
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• 2003

In South Korea, marine terraces have been well developed along the eastern coastal zone, and previous researches on the marine terraces have also been focused on to this coastal zone. The marine terraces of the eastern coast of South Korea had been classified into three terrace groups, that is, the higher, middle, and lower surface ones, according to the heights of marine terraces by previous studies(Oh, 1981 ;Chang, 1987 ;Yoon et. al, 1999, 2003 ; Hwang and Yoon, 1996 etc.). Recently, however, it tends to classify the marine terraces based on the concept of geomorphic surface units(Lee, 1987 ; Kim, 1990 ; Choi, S. 2003; Choi S. et. al 2003a,b, etc). For example, it was proposed that the marine terrace surfaces of Eupcheon coast of the southeastern coastal area of Korea could be classified into 16 geomorphic surfaces, i.e., Eupcheon 1terrace(former shoreline height of 160m), 2(153m), 3(140m), 4(130m), 5(124m), 6(115m), 7(100m), 8(92m), 9(82m), 10(71m), 11(62m), 12(53m), 13(43m), 14(35m), 15(18m) and 16(10m) surfaces, in descending order, according to the former shoreline heights(Choi, S, 2003 ; Choi, S. et. al, 2003a,b). Among these terraces, Eupcheon 1, 2, 4, 5 and 7 surfaces had not been reported in previous works. Among the above mentioned marine terraces, Eupcheon 15 terrace, the most widely and continuously distributed marine terrace have been identified as marine terrace of the Last Interglacial culmination period(oxygen isotope stage 5e) which was based on amino acid dates(124∼125ka BP) and geomorphological features such as red soil, pollen analysis, fossil cryogenic structures and crossing terrace concept. Eupoheon 15 terrace surfaces have also been proposed as the key surface for the identification and correlation of the so-called '5e' marine terrace in the eastern coast of South Korea. This terrace was reconfirmed as the Last Interglacial culmination period, which was based on the identification of Ata tephra, one of the wide-spread marker tephra which indicates the Last Interglacial culmination period in Japan by Sasaki et. al(2002). It was thought that marine terraces of the eastern coast of South Korea had been formed by the steady-state uplifting during the Quaternary glacio-eustatic sea level changes(Choi, 1997). The uprift rate of 10cm/1,000years had been proposed in the eastern coast of South Korea based on the former shoreline altitude(18m) of the above Eupcheon 15 terrace. Therefore, it can be estimated that Eupcheon 1 terrace had been formed in the early Pleistocene from the above uprift rate. The OSL dating for the samples of Eupcheon 7, 9, 13, 15 and 16 terraces and identification of marker tephra in the terrace deposits are in progress. It is expected that more elaborate chronology on themarine terraces of the eastern coast of South Korea could be established by these absolute dates and marker-tephra.

• Proceedings of the Korean Quaternary Association Conference
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• 2005.10a
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• pp.48-54
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• 2005

Terrace morphology is so conspicuous in the south eastern coastal areas. Coastal terraces can be divided into 5 main surfaces, including beach and coastal alluvial plain(AP, $4{\sim}5m$), Low Terrace(LT, 8 $^{\sim}$ 25m), Middle Terrace(MT, 36 $^{\sim}$ 55m), High Terrace(HT, 63 $^{\sim}$ 86m) and upper High Terrace(uHT, above 90m). Among them Lower Terrace Formation is distributed between 8m and 20m in altitude. Both Tephra deposited of LT2 formation and OSL datings of sand layers in LT 2 and LT 3 Formations support the age of the LT 2 formation is MIS 5d or 5e, most probably 5e. The age of LT 3 is interpreted MIS 5a, based on tephra production in organic mud layers and OSL dating of sand deposits just above the beach pebbles of the LT 3. Particularly the transgression, possibly equivalent to the well-known Monastirrian episode in the Mediterranean Sea.

• Journal of The Geomorphological Association of Korea
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• v.19 no.3
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• pp.97-108
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• 2012

During the last few decades, the ever-increasing knowledge of coastal morphogenic processes has made marine terraces the most recognizable, widespread and scientifically reliable records to determine both qualitatively and quantitatively the vertical movements that have affected the tectonically active coastal regions during the Quaternary. This study first aims to address the marine terrace records from Suje-ri to Suryum-ri along the coast of Gyeongju, SE Korea. Eight distinct flights of terraces, including HH YC, elevated up to 160 m above present sea level have been mapped along the coast of the study areas, and are designated $L_{II}$ to HH YC from the youngest to oldest. Based on the elevation of paleo-shoreline and inferred formation age for HH YC uplift rate since the middle Pleistocene has been estimated at 0.23 mm/year. Establishing the nature and timing of the uplift history derived from marine terraces provide a better understanding of neotectonic framework for explain enigmatic, complex landscape evolution in the Korean peninsula.

• Journal of the Korean Geographical Society
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• v.30 no.2
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• pp.103-119
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• 1995

This Paper aims to compare the lower marine terraces distributed from Muckho to Gangneung in the mid-eastern coast of Korean peninsula by the geomorphic method of using characteristies of terrace features and terrace deposits, paleosol, and fossil cryogenic structures, and to estimate the age of the lower marine terraces on the basis of the comparisons of those with the characteristics of thalassostatic terrace in adjacent rivers. The 1ower marine terraces in this area can be classified into two levels, i.e., lower marine terrace I and II surfaces, in desending order, according to the difference of former shoreline altitude. The former shoreline heights of the lowerm marine terrace I and II surfaces are 18m and 10m, respectiveiy. The width of the I surface is broader and distributed more continuousiy than that of II surface. Daejin I surface in Muckho coast, and Myeongju and Anin terrace in Gangneung coast could be classified into the lower marine terrace I surface, and Daejin II surfaCe into II surface. The Surface of ancient shore platform of the lower marine terrace I and II surfaces were weathered, and the color of the terrace deposit ranges from red to reddish brown. And this terrace deposit is covered with slope deposit of Last Glacial or fossil periglacial structures (platy structure and vecicle) of Last Glacial are formed in terrace deposit. These facts indicate that the lower marine terrace I and II surfaces had been formed before the Last Glacial, and then affected by chemical weathering under warm environment, finally followed by cold period. But the deposit of the lower marine terrace I surface is more weathered than that of II surface. And pseudogleyed red soil, which is developed in I but not in II surface, could be judged to have been formed in the Last Interglacial culmination stage (Oxygen isotope stage 5e). Therefore, in terms of the degree of weathering of the terrace deposit and the existence of pseudogleyed red soil, the age of both terrace is thought to be a little different. And the characteristics of the above mentioned II surface are accord with those of thalassostatic terrace formed in middle or late period of the Last Interglacial (5e or 5a). Thus on the basis of above all points, the lower marine terrace I and II surfaces in this area could be seen to have formed in the Last Interglacial culmination stage and middle or late period of the Last Interglacial, respectively. Because the lower mamine terrace I surface is broadry distributed in the eastern coast of Korea nPeninsula, the surface could be used to be a key surface in studying Quaternary marine terraces.

• Journal of the Korean Geographical Society
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• v.46 no.1
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• pp.1-19
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• 2011

The physical and chemical characteristics of loess-paleosol sequence in Jeongjang-ri, Geochang basin are examined using the magnetic susceptibility measurement, grain size analysis, OSL age dating, major, rare earth and trace elements analysis. The grain size characteristics of the loess-palesol sequence are obviously different from those of river sediment forming river terrace deposits and the Chinese Loess Plateau. The loess-paleosol sequence consisting of L1, L1LL1, L1S1, L1L2, S1 and L2 from top to bottom is estimated to MIS 2~MIS 6 and the river terrace to MIS 7. The compositions of major, rare earth and trace elements indicate that the sequence show more weathered characteristics than the Chinese Loess Plateau and originated from the Chinese Loess Plateau. These features are in harmony with the previous studies in Korea.

• KOMUNHWA
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• no.70
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• pp.35-62
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• 2007

Songguk-ri site gained academic recognition by the excavation of stone coffin tomb with a bronze dagger in 1974. And it is confirmed that this site is epoch-making in Korean bronze age through the following excavation started in 1975. But the excavation reports published until now do not have even overall view of this site, thus it is difficult to get the whole picture of this site. Thus, in this paper the author reexamined all reports on this site and by making the map of overall view and distribution of archaeological features as a basic research. Moreover, I analyzed also artifacts from this site, and compared with the recent papers written by other researchers about the chronology and character. Songguk-ri site has livelihood domain which consists of dwelling pits, attached features, storage pits, pot-firing features, wood fence, abatises, buildings above ground, as well as cemetery which consists of stone-coffins, jar-coffins, pit tombs. Trace of making large terrace was also excavated. These features seem to belong to the same archaeological stage, dated about B.C.850-550, according to C14 dating. On the other hand, the intensification of wet-rice cultivation made this group more productive. Based on this financial strength, some influential group emerged they constructed defensive settlement to protect their products safely. Besides it seems that there were frequent occurrence of conflicts. However, we can know that they kept their stable life, through the expansion of living space. Consequently, Songguk-ri site played a role of the summit among some settlement in this area.