• Journal of the Korean Geographical Society
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• v.34 no.1
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• pp.17-26
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• 1999

안성천의 중류인 안성읍 옥상리와 미양면 양지리에는 충적단구가 발달되어 있다. 충적단구와 인접한 범람원은 대개 점이적으로 만나지만 단구애를 통해 구분되기도 한다. 단구는 전반적으로 평평한 편이나 부분적으로 경사가 나타나기도 한다. 충적단구의 퇴적물 중 점토의 SiO2/Al2O3비와 SiO2/R2O3비를 계산한 결과, 라테라이트화 작용의 흔적이 나타나지 않는다. 이는 충적단구가 최후간빙기 이후에 형성되었음을 시사하는 것이다. 그리고 충적단구가 안성천 하구로부터 상당히 떨어져 있다는 사실을 고려하면 이들 단구가 기후단구일 가능성이 높은 것으로 생각된다.

• Journal of the Korean Geographical Society
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• v.37 no.3
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• pp.222-236
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• 2002

The Osip-cheon river flowing on the east side of the Taeback mts. has formed river terraces on the several heights along the middle- and downstream. The river terraces are classified into 5 climatic ones and 7 thalassostatic ones. The thalassostatic ones are found to the height of 145-l50m level at 20-30m intervals. These vertical distribution is caused by the continuous uplift and periodical rise and fall of the sea-level. The high higher surfaces among the thalassostatic ones are the highest among those of Korea. The chronologies of the terraces are correlated to the marine oxygen isotope stages : The thalassostatic terraces on the level of 40 m.a.s.l. are to the stage 7, 70 m.a.s.l.. to the stage 9, 90 m.a.s.l. to the stage 9, 110 m.a.s.1. to the stage 11 and those of 150 m.a.s.1. to the stage 15 among the Interglacial Ages. The landuses and geomorphic landscapes of the Samchok area are chracteristic, because the karst landforms, such as doline and uvala, are developed on the surfaces of the middle-, the higher- and the high higher surfaces of river terrace.

• Journal of the Korean Geographical Society
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• v.49 no.1
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• pp.1-17
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• 2014

This study estimates geomorphological processes of fluvial terraces by uplifts and bedrock features, by the analyses of topography, distribution, formation age and incision rate of fluvial terraces using Gwang-cheon River in Uljin, Namdae-cheon River in Pyeonghae and Osip-cheon River in Yeongdeok located in the southern Taebaek Mountain Range. The tectonic and climatic terraces I in the upper reaches of Gwang-cheon River with an altitude from riverbed of 9~12m indicate the formation age of MIS 2 with a incision rate of 0.40m/ka. However, the tectonic and climatic terraces I in the upper reaches of Osip-cheon River with an altitude from riverbed of 7~10m show the formation age of MIS 3 with an incision rate of 0.10m/ka. These results suggest that the uplift rate in the Gwang-cheon River basin is likely to be higher than that in the Osip-cheon River basin. Unlike the lower reaches of Osip-cheon River, the thalassostatic terraces are not found in the lower reaches of Gwang-cheon River, because the basin has low maintainable ability of landforms in river valley due to high uplift rate and bedrock properties resistant to weathering and erosion. On the other hand, the lowest tectonic and climatic terraces in the study areas indicate different formative ages and the terraces during the cooling stage in interglacial as well as during interstadial are also found. Therefore, this study suggests that chronological method for fluvial terrace by the previous developmental model of climatic terrace should be reconsidered.

• Journal of The Geomorphological Association of Korea
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• v.26 no.3
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• pp.19-30
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• 2019

This study summarizes domestic and foreign previous works on fluvial terrace with absolute ages to discuss formative process of climatic terrace in Korea. Different from traditional climatic terrace model, approximately three quarters from foreign works have argued that formation of climatic terrace can be attributed to medium- and short-term climatic change or other environmental factors, rather than long-term climatic change of glacial and interglacial cycles. Based on previous works on fluvial terrace in Korea, it can be suggested that fluvial terrace in Korea formed not due to long-term climatic change of 100,000-year cycles related to glacial and interglacial cycles, but due to medium- and short-term climatic change or climatic event of tens of thousands of years related to intensity change in summer monsoon, one of the important factors affecting precipitation in Korea.

• Journal of The Geomorphological Association of Korea
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• v.18 no.4
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• pp.17-33
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• 2011

This study summarizes the research history of fluvial terraces in Korea and examines the geomorphic properties of fluvial terraces in Korea based on the previous works. The research history of fluvial terraces in Korea can be divided into the three periods. The theories of fluvial terraces were spread by the early geomorphologists during the period of Japanese colonial era to mid-1980s. The dissertations on the fluvial terraces were intensively published during the late 1980s to 1990s and their discussions were the center of geomorphology researches in Korea. Since 2000s, the discussions have become more mature and researches have been quantitatively increased as the various methodologies have been developed. The fluvial terraces in Korea are mostly developed in the western and eastern parts of the Taebaek Mountains, upper and middle reaches of Han and Nakdong River, and in the western slopes of Sobaek Mountains, middle reaches of Namhan River, upper and middle reaches of Geum and Seomjin River. Along these rivers in actively uplifted areas, fluvial terraces with much higher altitude from riverbed are observable and incision rates are relatively high. In the sense of the formation ages, they have developed in not regular patterns by the climatic changes during the Quaternary, but in more complicated aspects by the environmental conditions such as climate, hydrology, geology and geomorphology in the specific drainage basins.

• The Korean Journal of Quaternary Research
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• v.25 no.1
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• pp.1-13
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• 2011

To reinterpret the meaning of fluvial terraces in the Quaternary researches, the concepts and geomorphic properties of fluvial terraces are reviewed. Fluvial terraces are the alluvial landform that was once river channel or floodplain by paleochannel flowed in elevated areas from the current river by active incision of rivers due to the climatic changes and/or uplifts. As fluvial terraces are the remnants of alluviums after incisions of rivers, the major factors influencing on the incisions are the falling of erosion base, increase of river discharge and distinct geomorphic phenomenon of river. While it is generally known that fluvial terraces deposits in the upper or middle reaches of large rivers were formed during glacial periods, the deposits may be formed at the various periods due to the diverse natural environments and geomorphic properties of specific rivers, because there have been numerous cases that the ages of fluvial terraces in the upper or middle reaches of large rivers in Korea and China can be correlated to the interglacial periods.

• Journal of the Korean Geographical Society
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• v.35 no.2
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• pp.159-176
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• 2000

본 연구는 남한강 상류의 소지류인 쌍천 유역에 발달한 하성단구의 퇴적물을 모재로 발달한 토양 특성을 조사.분석하였다. 중위 단구의 A1층은 갈색(10YR 4/3)의 미사질토양이고 발달도가 낮은 입상구조이며 B1층은 황갈색(10YR 5/8)의 사질식양토로 아각괴상구조이다. 고위단구의 A1층은 옅은 적갈색(5YR 4/3)의 미사질양토 내지 황갈색(10YR 5/8)의 미사질식토로 발달도가 낮은 아각괴상구조이다. B1층은 적색(2.5YR 3/6)의 사질식토 내지 밝은 적갈색(2.5YR 4/6)의 식양토로 발달도가 양호한 아각괴상구조이다. 고위단구 퇴적층을 모재로 발달한 토양의 구조는 중정도의아각괴상구조이고 조직이 치밀하다. 토양은 A1층, B1층,B2층으로 되어 있으며 또한 B층은 점토가 집적되어 있고 점토 피막이 나타난다. 쌍천의 중위단구상에 발달한 토양은 황갈색토이고 고위 단구상의 토양은 적색토이다. 고위단구 퇴적물을 모재로 발달한 본 적색토는 생성시가가 민델-리스 간빙기의 이전에 생성된 것으로 현재보다 온난한 생물-기후 조건하에서 탈규산화를 동반하는 적색토화작용에 의해 형성된 것으로 추정된다. 고위단구에 발달한 적색토는 토양단면의 형태적 및 물리 화학적인 특성등으로 보아 고적색토로 분류된다.

• Journal of the Korean association of regional geographers
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• v.7 no.2
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• pp.71-81
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• 2001

According to the change of stream power/resisting power relationship due to the crustal movement or the climatic change, most channel landforms which reflect the equilibrium state of fluvial system are eroded and a part of them is remained as a river terrace. In many rivers in Korea are extensively distributed the relatively younger low river terraces. But their accurate formation mechanism is not known. In this paper, the formation processes and the dating of low river terraces distributed in Nakdong River basin will be investigated. Stream power of the downward erosion was revived because the sea level fell down. So stream power was superior to the resisting power under the cool-wet climatic condition during the last glacial period. Thus the river bed was excavated deeply, so that low river terraces were built up. And many incised meander loops were cut during this period. But, when fluvial system did not have equilibrium over all reaches, the last glacial period ended and the sea level initiated to rise rapidly. The headward erosion from the fall of sea level during the last glacial period had kept up to Hagye Fall because of the cutting of incised meander loops. Deeply excavated valleys and abandoned channel of cut-meander in lower reaches of a stream were filled with sediments. Thus the longitudinal profile of the uppermost reaches reflect the last interglacial, the upper reaches the last glacial, and the middle/1ower reaches recent fluvial system. Therefore low river terraces have been formed since the last glacial period.

• Journal of The Geomorphological Association of Korea
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• v.20 no.1
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• pp.57-74
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• 2013

Coastal terrace was developed at 8.3m height near Waon village in Suncheon-si. Due to the sandgravel layer deposited in a different today's environments, rounded gravel(4.3m, 5.8m, 6.3m) sequentially in a cross-section of coastal terrace, so it provides a good example which understand Holocene sea level changes to determine the effect on the various climatic-environments traits. For the purpose of identifying the morphogenetic process, Profile description, Grain size, XRD, Thin section analysis was attempted. As a result, coastal terrace are more likely to have been formed by the more recent period rather than the last interglacial(MIS 5 period), and at that time, various pedological features are considered to be formed.

• Journal of the Korean Geographical Society
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• v.42 no.3 s.120
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• pp.388-404
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• 2007

This study interprets evolution of fluvial terraces along the four Yeongdong- and Yeongseo streams such as Naerin River, Yeongok River, Golji River and Osip River, in Gangwon Province based on the tectonics. The results from the analyses of the distribution pattern of fluvial terraces and incision rates of rivers show distinctively the evidence as the axis of uplift by Taebaek Mountains, especially on the 4th, 5th and 6th terraces in upper reach of Osip River among the four streams. The axis of uplift extends to the zone of $30\sim40km$ in width as well as the divide. The difference of uplift between upper and middle reaches of Naerin River and total reach of Golji River wasn't found from the height from riverbed by the active uplifting along all reaches, estimated to be set in inner area of uplift zone. Incision rate of period between formation age of 2nd terrace and 1st terrace is calculated $0.13\sim0.22m/ka$, and incision rate of period between formation age of 1st terrace and Present is diversely calculated $0.17\sim0.27m/ka$ by the climatic discrepancy between the two periods. The incision rate of Yeongdong streams whose mouths reach to the sea level eroded actively more than Yeongseo streams in the uplift zone. And Yeongdong streams between formation age of 1th terrace and present appears to much higher than that of Yeongseo streams, due to active down-cutting in oder to balance against the sea level.