• Journal of the Korean Geographical Society
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• v.31 no.3
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• pp.613-629
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• 1996

River terraces of glacial and interglacial periods are most developed in the Ungcheon River, midwestern coastal region of south Korea. Among these terraces, interglacial river terraces correspond to the thalassostatic terraces of eastern coastal region of Korea. Thus the former shoreline altitudes of the coastal region around Ungcheon River can be estimated by using relative heights of these interglacial thalassostatic terraces of Ungcheon River The former shoreline altitudes estimated from interglacial thalassostatic terraces of Ungcheon River are 80m, 50${\sim}$60m, 40${\sim}$45m, 30m, 25m(?), 15${\sim}$20m, and 10m. These estimates are almost identical with those of Quaternary sea levels of eastern coastal region. Among the above estimates of Ungcheon River, the former shoreline altituded of 15~20m and 10m correspond to the ancient sea levels of $\pm$18m and $\pm$10m of eastern coastal region which were injudged as the last interglacial culmination period and late warmer period of the last interglacia(5e and 5a substages of oxygen isotope stage), respectively. Therefore there is a possibility that the rest of the above former shoreline altitudes of the coastal region aroune Jngcheon River also correspond to those of eastern coastal region. On the basis of the above possibility it can be proposed that the eastern and western coastal region of Korean Peninsula have undergone tectonic uplift of equall amount since the middle Quaternary Period.

• Journal of the Korean earth science society
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• v.36 no.6
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• pp.512-519
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• 2015

Although Quaternary marine terraces and onshore paleo-shoreline records provide clues to our understanding for the mode and nature of neotectonics in the Korean peninsula, it cannot be accomplished without knowledge on both independent information of the past sea level records and tectonic deformation field together with precise results of numerical dating for higher terraces. This study reported cosmogenic radionuclides ($^{10}Be$) dating results conducted in higher terraces in the eastern and western coasts of the Korean peninsula. As a result, the measured concentration ratio of $^9Be/^{10}Be$ and the exposure ages were much younger than expected. It implies that either there is possibility of error in experimental processes or the samples experienced a complex exposure history probably included a burial at some stage. Considering the past climatic conditions around the Korean peninsula and a possible complex exposure history after the emergence of marine terrace, the discovery of a suitable study area and a sampling site are an essential part of successful $^{10}Be$ dating technique.

• Journal of the Korean Geographical Society
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• v.39 no.1
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• pp.27-44
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• 2004

Upper reach of Soyang River at the northernmost area around Taebaek Mountains in South korea is profitable area to understand paleo-environment during the Quaternary such as tectonic process and climate change in the Korean Peninsula. This study explained paleo-environment affect to channel development by geomorphic distribution and characteristics of terrace surfaces, and analysis of deposits at 58 fluvial terraces in upper reach of Soyang River. Fluvial terraces were classified from T1 to T6. Most terraces are distributed on the point bar in meandering channel and one side along river valley. Terraces tend to decrease in number and superficial dissection rate to be higher and channel slope to be steeper if it takes long time from T1 to 6. The paleo-channel of Soyang River is supposed to be stronger meandering in period of T2 than T3. The weathering rind of gravel is generally thicker in older terrace, however, differs by contents of water and air in deposits. Based on the data of stratigraphy, grain size analysis, pollen analysis and rubification index in deposit, formation age of T5 terrace in Soyang River are estimated in MIS(Marine Oxygen Isotope Stage) 10, and T2 terrace are estimated in MIS 6.

• Journal of The Geomorphological Association of Korea
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• v.15 no.2
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• pp.1-9
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• 2008

This studied area is divided into the mountains and the valleys. The former is nearly consisted of the badland, the latter is consisted of alluvial plains in the valley, fluvial terrace at the side of the river, alluvial fans between mountains and river terrace. There are many tors, mushroom rocks, sugarloaves, weathering pits, castle coppies, columnar rocks, pinnacles, balanced rocks carved on tuff by means of erosion in the Chiricahua Nat'l Monument. Willcox Playa is alkalic crust where was lake in pleistocene epoch at the time wetter than present. Alkalic crust was made of Ca, Na, K etc. There are sand dunes around here where was lake side in the past. We found many kinds of fossils at the 2,000ft thick horizons of valley alluvium. Pediment and alluvium bordered at the base of Mt. Dragoon wavily. Exfoliation and spalling and sheeting resulted in boulders around here. Tucson is alluvial plain filled in thick 7,0000ft valley. Volcano, fault, erosion, alluvium were and are processing in this area.

• Journal of the Korean Geographical Society
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• v.44 no.4
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• pp.463-480
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• 2009

The weathering properties and provenance of loess-paleosol sequence deposited on gravel layer of river terrace in Bongdong-eup, Wangju-gun, Jeonbuk Province are examined using soil analysis, magnetic susceptibility measurement, grain size and element analysis. The Bongdong section consists of, from top to bottom, Layer 1(paleosol), Layer 2(loess), Layer 3(paleosol) and the gravel layer of river terrace. The magnetic susceptibility values show the systematic variations in the sequence and the results of grain size analysis reveal that the sequence was deposited by not fluvial or slope process, but eolian process, and that contains finer materials than the Daecheon loess and Chinese Loess Plateau. Among the results of soil analysis, organic contents indicate systematic variations similar to the magnetic susceptibility. The wet soil colors further reflect the characteristics of the sequence rather than the dry soil colors. Based on the analytical results of major and rare earth elements, the eolian materials contained in the sequence were deposited by the materials originated from the areas where the Chinese Loess Plateau has been originated or the reworked materials from the Chinese Loess Plateau, and after the depositions, the materials experienced the intensive chemical weathering under the humid-warm climatic conditions in the Korean Peninsula.

• Journal of the Korean association of regional geographers
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• v.5 no.2
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• pp.133-142
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• 1999

The wetland is very important ecologically as a habitat of diverse organisms. The purpose of this paper is to elucidate the morphogenetic environment of Jilmoe Bog found in the Odae Mountain National Park Jilmoe Bog is located in the high etchplain(1,060m) where Daebo Granite which had intruded in Jura epoch of Mesozoic era has weathered deeply and has uplifted in the Tertiary. The annual mean temperature of study area is $5.3^{\circ}C$, the annual precipitation is 2,888mm. The minimun temperature of the coldest month(january) is below $-30^{\circ}C$ and the depth of frozen soil is over 1.6m. Jilmoe bog consists of a large bog and a small bog. The length of the large bog is 63m and its width is 42m. The basal surface of Jilmoe bog is uneven. Jilmoe bog is a string bog fanned due to frost actions. In String bog, its surface is wavy with stepped dry hills and net-like troughs crossing hill slope. It seems that string bog is related to the permofrost or seasonal permofrost of cold conifer forest(taiga) zone(where the depth of frozen soil is very deep in the least in winters). String bog is a kind of thermokarst that frozen soil thaws differentially locally in declining permofrost and ground surface becomes irregular. There is turf-banked terracette of width $30{\sim}40cm$ in the headwall of small cirque-type nivation hollow formed at footslope of Maebong mountain around Jilmoe bog. This turf-banked terracette is formed by the frost growth of soil water below grass mat in periglacial climate environment. Where water is plentiful such as a nivation follow${\sim}$valley corridor and a headwall of valley, turf patterned grounds of width $30{\sim}50cm$ are found. This turf patterned ground is 'unclassified patterned ground', earth hummock. In conclusion, Jilmoe bog is a string bog of thermokarst that the relief of ground surface is irregular according to locally differentially thawing of permofrost(frozen soil). Jilmoe bog is high moor, its surroundings belongs to periglacial environment that turf-banked terracette and turf patterned ground are fanned actively.

• Journal of the Korean association of regional geographers
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• v.15 no.2
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• pp.192-203
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• 2009

The purpose of this paper is to elucidate the formative processes of depositional landforms in Jiwoo drainage basin which located in the most upstream reach of Namgang River. Through the analysis of morphologic characteristics and sedimentary facies, the formative processes can be summarized as follow: First, the high depositional landforms(Sapyeong, Eungam, Naedongdyttle site) were formed by gelifluction process in the periglacial environment during the last glacial period. And the relative height over river bed of them is getting lower from upper to downstream. The extent of the high depositional landforms is assumed about 1 kilometer downstream far from the confluence of Jiwoo stream and Namgang River. Second, the sediments in the gentle slope at Jangseungbuldle were carried by gelifluction process during the last glacial stage after the deep-weathered bedrock had formed a gentle slope. Third, the high depositional landforms were dissected during warm and humid environment of postglacial stage, and some sediments of them were left in the river bed. Later, as the more upstream high depositional landforms were dissected completely, stream power was getting more than resistance(sediment storage) and the low depositional landforms(Sapyeong, Yongchusa, Deungbangdle site) were formed.

• Journal of the Korean association of regional geographers
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• v.18 no.3
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• pp.253-267
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• 2012

The study looked into the type and characteristics of debris landforms in Mt. Mudeung. By focusing on the representative area, we aimed to categorize the debris landforms based on the morphologic and genetic characteristcis. The types of debris areas in Mt. Mudeung can be divided into the exposed debris type, mixed type of matrix, and the boulder-hidden type. Supply of block in the debris slope area displays different features depending on types of rocks. For the stony slopes of andesite, the block must be moved from the columnar joint or cliff in the upper part. The andesite debris slopes display dominant edge shape while displaying no round shape. The granite stony slopes display dominant round shape and the present exposed slope was assumed to be formed as the core stone which was deep weathered moved along slope during the periglacial era and the matrix was removed after post-glacial era. The movements of blocks are assumed to be caused by solifluction process. The joint area where granite and andesite areas meet, granite is located beneath andesite area, and this implies that blocks were actively freezing and creeping by solifluction and freezing and thawing at that time. It can be assumes that the granite matrix formed plain slope and then andesite boulder covered up the slope. Currently, the blocks in the stony slopes of Mt. Mudeung shows almost no mobility and the stony slopes created under periglacial climate can be considered to be fossil landform.

• Journal of The Geomorphological Association of Korea
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• v.15 no.2
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• pp.11-24
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• 2008

Stratified slope was formed on the SSE-facing slope in the southwest region of Haenam, South Korea. Field and laboratory investigations into the geomorphology and sedimentology of stratified slope deposit that is inactive. Outcrops of this deposit show an alteration of coarse debris-supported matrix and tiny debris-supported matrix layers. Sedimentological analysis(particle-size analysis) indicates that this deposit is not fluvial process or only gravitation like rock-fall. Many clasts and fine materials on the slope is supposed to be product by congelifraction under Pleistocene periglacial climatic environment. Also The processes responsible for the genesis of this deposit probably are to move downward by gelifluction and to remove fine materials by slope wash in thawing cycle and in situ debris congelifraction on gelifluction slope. Now It is impossible to account for the time range of genesis(diurnal, seasonal). In conclusion, this stratified slope formed in cold and humid periglacial environmental in pleistocene, therefore, this slope is a periglacial relic landform, indicates that in south korea there was a cold and humid paleo-climate such as periglacial environmen.

• Korean Journal of Soil Science and Fertilizer
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• v.19 no.4
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• pp.275-282
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• 1986

A series of studies on the properties of clayey terrace soils distributed at the inland (Yeongcheon) and coastal (Yeongjil) regions in Yeongnam district was carried out. On the base of the facts found and already reported about the macro morphological features as well as on pedological characters in micro scale, physicochemical properties, mineralogical characteristics etc., the present study dealt with soil genesis and tried to classify the soils for reasonable use and managements. 1. Although the both regions belonged to "Mesic" soil temperature regime and "red and yellow earths" areas of "Thornthwaite" pedo-climatic diagram, climatic indices as a soil forming factor indicate that the coastal Yeongil had milder than the inland Yeongcheon. 2. All the terrace soils had developed soil profiles with an "Argrllic B". Upyeong soils in Yeongil region had "Argillans" even in the "II B horizons" that possibly be "Paleo-argillic". 3. The bisequum profiles of Bancheon in Yeongcheon and Upyeong in Yeongil revealed that they were developed on Late Mesozoic shale and on semiconsolidated Tertiary deposits respectively, therefore the overlying clayey terrace deposits were assumed to be originated from the Early Quaternary deposits, Diluvium. 4. To supplement the Soil Taxonomy of USDA, the terrace soils with different degrees of gleyzation were classified as follows; Deogpyeong and Hwadong soils which have less than 50cm of paddified gley horizons (redness less than 0.5) in the upper part of the profiles by artificial surface irrigation, tentatively classified into "Anthrepiaquic Hapludalfs" and the Geugrag soils that have more than 50cm of paddified gley horizons within 1.2m of the profiles, into "Anthr-aquic Ochraqualfs" while the Upyeong soils that had greyish mottles in subsoils by natural ground water remain as an "Aquic Hapludalfs" the same as present. The Bancheon soils with free mottles are into "Typic Hapludalfs" as used at present.