• Journal of The Geomorphological Association of Korea
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• v.19 no.1
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• pp.57-68
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• 2012

Red saprolites are appeared in granitic hills in Naju, Southern Korean Peninsula. These red saprolites were analyzed for their geochemistry, including CIA, A-CN-K and A-CNK-FM ternary plots, to understand the chemical weathering trend and rubefaction of the saprolites. These saprolites were compared with kaolinitic saprolites of Guadalquivir Basin in Spain formed under paleo-humid tropical conditions. Chemical Index of Alteration(CIA) value for Naju in Korea is 80, and 87 in Guadalquivir, suggesting moderate and strong weathering in both. Relative to kaolinitic saprolite of Guadalquivir in Spain, red saprolites in Naju are commonly weak loss of CaO, $Na_2O$, especially in $K_2O$. The A-CNK-FM ternary plots of Naju saprolites relative to Kaolinitic saprolites of Guadalquivir shows weak chemical alteration owing to slow removal of $K_2O$, but high mafic constituents, $Fe_2O_3$ and MgO, for most of the samples. In the saprolites of Naju, mafic oxides, $Fe_2O_3$ and MgO, become enriched because of the fast and massive removal of CaO, $Na_2O$ and $K_2O$ relative to other elements, resulting in rubefaction of the surface layer of the saprolites, so more redness than kaolinitic saprolites of Guadalquivir. It is found that the rubefaction of the saprolites is not necessarily proportional to chemical weathering intensity.

• Journal of The Geomorphological Association of Korea
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• v.19 no.1
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• pp.41-56
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• 2012

The purpose of this study is to look into the location environment of prehistoric and ancient remains (hereinafter referred as remains) in Daejeon Area. For the purpose of this, out of remains reported in investigation areas so far with the object of remains (total 22 places) of New Stone Age -Proto Three Kingdom period, geographical and Geomorphological analysis was conducted. The results are like the following. Most of the remains are distributed over hills especially flat surface - semi-gentle slope of hills. The bed rocks of the remains (21 places, about 95%) are composed of double-mica granite. The remains (19 places, 86%) retain 'the 1st-2nd small scale river and '5th or higher medium scale river'within comparatively short distance at the same time. The average altitude of remains is 71m and most remains are located over the altitude of 50 - 90m. The average gradient of hillslop where the remains are located is $6.7^{\circ}$ and the remains (15 places, 71%) are located over the gradient of about $0-15^{\circ}$. And the tendency that the higher the gradient of remains the smaller the number of remains was confirmed. From the above, it is judged that the inhabitants who lived in Daejeon Area at that time preferred hills with comparatively not high altitude and the earth's surface of low gradient and in addition they recognized water (river) as being important when they selected the location of settlement (or dwelling sites group).

• Journal of The Geomorphological Association of Korea
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• v.18 no.2
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• pp.25-37
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• 2011

The purpose of this study is to investigate the history of phenomenon(hereinafter called mass-movement) of movement of inorganic material originated from hillslope by denudation of hillslope surrounding the watershed during Holocen period in the Chaamgol watershed(hereinafter called study watershed) uppermost stream of Maegokcheon Cheonan-si Chungnam. To do this, for the object of allivium distributed in valley bottom of study watershed, facies analysis, radiocarbon dating and grain size analysis were conducted and geomorphological analysis on study watershed conducted together. The result is like the following. It was confirmed that over around 9,100yrBP~to recent due to a few times of mass-movement occurred in time scale of 10²~10³ years, a large quantity of inorganic material is mixed in organic material layer originated from wetland formed in valley bottom of study watershed or exists between organic material layers. And it was found that in study watershed, mass-movement occurred in instable period of hillslope after the Early Holocen existed at least 8 times (M1 period~M8 period) and wetland environment formed in the stable period of hill slope existed total 4 times (W1 period~W4 period). This analysis result will be used in the future as basic material in research of Holocen climate change of Maegokcheon watershed and in restoration of denudation process of hillslope following this.

• Journal of The Geomorphological Association of Korea
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• v.20 no.4
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• pp.51-70
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• 2013

The characteristics of deposits formed by the Daejon-cheon and Soobuk-cheon, dissecting the mountains such as Byungpung Mt. and Samin Mt. in western part of Damyang county, Jeonmam province. Results from field survey and bore hole logging by KIGAM are used in interpreting depositional environment, in this study. By the result of deposits near of the channels Daejon-cheon and Soobuk-cheon, and main channel of Youngsan River, the depth of sediment layers in this area is 4~7m, far thinner than formerly estimated. Weathered material of local rocks forms the base of the sedimentary layers. It can be assumed that the location channel of the Youngsan river has been stable ever since the start of the sedimentary events. Sediment particles of tributaries are angular than those of Youngsan River. Particles are larger and sorting is poor. It is interpreted as mount flash flood deposits. Main sources of sediments at the valley bottom or deposition dominated area are the terrace deposits or slope deposits over the gentle foot-slope or front of surrounding mountains. Some particles show polygonal cracking on the surface originated from the strong chemical weathering, while most of these has high angularity. It means various geomorphic processes operate to produce and transport the particles in this area.Isolated hills within the sedimentary plains are made with weathered materials of local bedrock. In the case of foot-slope of the hills, thin sedimentary layers are found. So it can be concluded that surface features of deposition zone of the Daejon-cheon and Soobuk-cheon is formed by the filling of lower part of the valley and its feature partly controlled by the relief of the weathering front.

• Proceedings of the Korean Geotechical Society Conference
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• 2004.03a
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• pp.176-187
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• 2004

서울ㆍ경기지역은 한반도의 서부중앙지역으로 동경 126$^{\circ}$와 127$^{\circ}$, 북위 36$^{\circ}$와 38$^{\circ}$ 사이에 위치해 있으며, 면적은 서울 605$\textrm{km}^2$, 경기도 10,184$\textrm{km}^2$를 차지한다. 북쪽으로는 휴전선, 서쪽으로는 서해, 동쪽으로는 강원도, 남쪽으로는 충청도와 접하고 있으며 한강에 의해 남북지역으로 나뉘어져 한 수 이북은 산간지역이 한 수 이남지역에는 평야지대가 발달하고 있다. 지형은 대체로 추가령 구조곡을 경계로 북부산지와 남부산지로 나누어지는데, 북부는 중국 요동방향의 마식령산맥, 남부는 중국방향의 광주산맥과 차령산맥이 각각 그 골간을 이루고 있으며, 서쪽해안에 가까워질수록 고도가 낮아져 평야나 구릉성 산지로 바뀐다.(중략)

• Journal of The Geomorphological Association of Korea
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• v.15 no.2
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• pp.67-83
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• 2008

To find out the process of hillslope denudation since the Last Glacial Maximum in Asan area, we conducted the stratiform interpretation and carbon age measurements with the collected samples through trenching in the valley bottom of 'Agol' located in the lower stream of Magok stream. The results are as follows. 11 inorganic and 8 organic matter layers were confirmed at the point of trench MG1 in the subject area, 7 inorganic and 3 organic at the point of trench MG2, and 5 inorganic and 3 organic at the point of trench MG3, respectively. The frequency of hillslope denudation, hillslope mass movement, which had occurred in the unstable environment of back hillslope at the point of MG 1, was 11 times (8 times before about 2,900yrBP, twice in between about 2,900~1,900yrBP, and once after about 1,900yrBP) as a whole. The frequency of moor which had formed in the comparatively stable environment of back hillslope was 9 times (5 times before about 3,000yrBP, twice in between 3,000~2,800yrBP, and once in between 2,200~1,900yrBP) at minimum. The frequency of back hillslope denudation at the point of MG2 was totally 7 times (4 times before about 1,900yrBP and 3 times after about 1,900yrBP) and the moor formations were 3 times (twice before about 1,900yrBP and once after 1,900yrBP). The frequency of back hillslope denudation at the point of MG3 was totally 5 times (3 times before about 1,900yrBP and twice after about 1,900yrBP) and the moor formations were 3 times (twice before about 1,900yrBP and once after 1,900yrBP). The hillslope surrounded by valley bottom of 'Agol' was confirmed as the pile up of various inorganic matters by the mass movement such as sand or sandy gravel in the valley bottom of the subject area, formed not once but several times of denudation. We could know that the hillslope denudation cycle converged to the time period of $10^2{\sim}10^3$ years. These results will be an important basic data for restoring hillslope denudation process near Asan and changing climate of the Late Quaternary Period.

• Journal of the Korean Association of Geographic Information Studies
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• v.11 no.1
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• pp.58-67
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• 2008

Topography factors, as homeostasis variables at forest fire, affect the formation of fuel load patterns, atmospheric phenomena and forest fire behavior. Examination of the correlation between landforms and fire severity is important to decision making for fire hazard analysis and fighting strategies. In this study, fire severity was analyzed using Normalized Burn Ratio(NBR) derived from pre- and post-fire Landsat TM/+ETM images and landform were classified based on Topographic Position Index(TPI) in Samcheok(2000), Cheongyang(2002), and Yangyang(2005) forest fire regions. F-tests and Duncan's multi-range test between landform and fire severity showed that fire severities of headwater, high ridges, and upper slopes is higher than ones of local ridges, midslope ridges, and plains. Fire severity were more sensitive in coniferous forest than broadleaf forests.

• Journal of The Geomorphological Association of Korea
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• v.18 no.4
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• pp.261-270
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• 2011

This study is to describe morphological linear anomalies manifested in the geomorphological landscapes of Woongcheon river-basin, situated in the western ends of Charyong Mountainous Range, and to elucidate their morphotectonic significance. The order of decreasing valley scale in the study area is NE-SW, NNE-SSW, NNW-SSE, N-S, and E-W series. The valleys of NE-SW lineament appear as the largest in the study area, having piedmont slope, terraces, low-relif hills. NNE-SSW lineament cross obliquely the geomorphological elements of the precedent lineament. NNW-SSE, N-S and E-W lineament cut the forms of higher orders showing NE-SW and NNE-SSW lineament. Scale of the linear valleys is not correlated with the order of streams. It is paradoxal that great valleys are not associated with the rivers of highest order. It owes to adaption of regional discharge system along the valleys exploiting the fracture resulted from succeeding tectonic accidents.

• Korean Journal of Heritage: History & Science
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• v.51 no.2
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• pp.22-37
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• 2018

Unmanned aerial vehicles (UAV) have attracted considerable attention both at home and abroad. The UAV is equipped with a camera that shoots images, which is advantageous for access to areas where archaeological investigations are not possible. Moreover, it is possible to acquire three-dimensional spatial image information by modeling the terrain through aerial photographing, and it is possible to specify the interpretation of the terrain of the survey area. In addition, if we understand the change of the terrain through comparison with past aerial photographs, it will be very helpful to grasp the existence of the ruins. The terrain modeling for searching these remains can be divided into two parts. First, we acquire the aerial photographs of the current terrain using the drone. Then, using image registration and post-processing, we complete the image-joining and terrain-modeling using past aerial photographs. The completed modeled terrain can be used to derive several analytical results. In the present terrain modeling, terrain analysis such as DSM, DTM, and altitude analysis can be performed to roughly grasp the characteristics of the change in the form, quality, and micro-topography. Past terrain modeling of aerial photographs allows us to understand the shape of landforms and micro-topography in wetlands. When verified with actual findings and overlapping data on the modelling of each terrain, it is believed that changes in hill shapes and buried Microform can be identified as helpful when used in low-flying applications. Thus, modeling data using aerial photographs is useful for identifying the reasons for the inability to carry out archaeological surveys, the existence of terrain and ruins in a wide area, and to discuss the preservation process of the ruins. Furthermore, it is possible to provide various themes, such as cadastral maps and land use maps, through comparison of past and present topographical data. However, it is certain that it will function as a new investigation methodology for the exploration of ruins in order to discover archaeological cultural properties.

• Journal of the Korean association of regional geographers
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• v.12 no.4
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• pp.449-460
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• 2006

This study aims to analyze distribution of natural lakes including lagoonal lake(lagoon) and tributary dammed lake(tributary lake) and calculate the size, morphology in order to interpret time-serial change of lakes using methodology of remote sensing images(1990s), GIS and topographic maps(1920s) in east coast of Korean Peninsular. Analysis results show that in 1990s, there are 57 natural lakes, with the total size of $75.62km^2$ over size $0.01km^2$. marine-origin lagoons are 48 with total size of $64.85km^2$, composing 85% of total natural lake, and the largest lagoon is Beonpo in Raseon City. Tributary lakes have been formed by damming of tributary channels by fluvial sand bars from main stream, located nearby at coastal zone, similar to lagoon sites. Large tributary lake, Jangyeonho, is developed in lava plateau dissection valley of Eorang Gun, Hamnam Province. There are more distributed at Duman River mouth$\sim$Cheongjin City, Heungnam City$\sim$Hodo Peninsular and Anbyeon Gun$\sim$Gangreung City. Geomorphometrically, correlation of size to circumference is very high, but correlation of size to shape irregularity is very low. The direction of lagoonal coast, NW-SE and NE-SW are predominated due to direction of tectonic structure and longshore currents. The length of the river into lake are generally short, maximum under 15km, and lake size is smaller, degree of size decreasing is higher. Geomorphic patterns of the lake location are classified as coast-hill range, coastal plain, coastal plain-channel valley, coastal plain-hill range and channel valley-hill range. During from 1920s to 1990s, change with lake size decreasing is highest at coastal plain-channel valley, next is coastal plain. Causes of the size decreasing are fluvial deposition from upper rivers and human impacts such as reclamation.