• Proceedings of the KSRS Conference
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• 2004.10a
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• pp.264-267
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• 2004

In identifying flood vulnerable areas, three methods are generally deployed: the geomorphology method which is based on topographic features; the past evidence method based on observed data of past actual floods; and, prediction of flood areas through hydrologic models. This study aims to improve the prediction model of the geomorphology method through the application of fuzzy method in GIS modeling. The generally used GIS method of superimposing thematic map layers assumes crisp boundaries of the layers, which results in either risk-averse solutions or risk-taking solutions. The introduction of fuzzy concepts to processing of evaluation criteria (DEM, slope, aspect) solves this problem. As the result of applying the fuzzy method to a test site in the west Nak-Dong river, similar flood vulnerable areas were predicted as when using the conventional Boolean criteria. The resulting map, however, showed varying degree of uncertainty of flooding in these areas. This extra information is deemed to be valuable in taking phased actions during flood response, leading to a more effective and timely decision-making.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.16 no.2
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• pp.53-69
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• 2011

Classification of estuaries based on their multi-component and multidisciplinary processes is important for the systematic management of estuaries. In this study, an integrated GlS-based analysis system including high resolution aerial photographies and topographic maps was used to classify 463 estuaries based on estuarine circulation pattern, geomorphological feature, natural habitat distribution and characteristics of land use. These estuaries were divided into two basic types, open and closed. Two hundred and thirty five systems were open estuaries comprising of forty one mountainous type (OM), eighty sevcn sandpit type (OS) and one hundred seven funnel type (OF). Each type of open estuary was further classified into three types based on habitat distribution and land use characteristics resulting in total ninc types of open estuaries. Two hundred and twenty eight estuaries were closed systems comprising of one hundred and forty four blocked type (CB directly) and eighty four lake type (CL, indirectly). CB type estuary was further classified into three types based on habitat distribution and land use characteristics. This estuarine classification scheme can be applied to provide a framework for effective management strategies of individual estuaries to estimate the management priority and strategy.

• 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.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.

• Journal of the Korean earth science society
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• v.43 no.6
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• pp.749-761
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• 2022

As the number of National and UNESCO Global Geoparks has increased, awareness of geological heritage and local government interests have also increased. In this study, data from the geological heritage sites in the Ulsan area were summarized, a practical use plan for geological heritage was prepared based on the assessment results, and the expected effects were also presented. The value for 33 of 112 geological heritage sites identified through literature surveys was evaluated. In terms of the geological heritage types in Ulsan, there were two geological, one geomorphological, and thirty mixed-heritage sites. In the context of the geological heritage of Ulsan, rivers and coastal topography were found to be dominant, and various geomorphological and geological features, such as fossils, folds, faults, shear zones, minerals, and ore deposits are included. Based on the assessment results, there were three, eighteen, nine, and three sites in Classes I, II, III, and IV, respectively. Considering the intrinsic and subsidiary values of geological heritage, the Gangdong Coast, Jujeon Coast, Taehwagang area, Daewangam area, the Daegokri-Cheonjeonri track sites, and Mujechineup are likely to be listed as potential geosites. When the endorsement of the geopark has been promoted alongside these geosites, it can contribute to the sustainable preservation and maintenance of the geosites, satisfy the demand for science education through geo-education, and support the sustainable development of the local economy following the detailed standards for geopark certification in the Natural Parks Act. This is expected to increase the brand value of Ulsan Metropolitan City.

• Journal of the Korean Geographical Society
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• v.49 no.5
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• pp.639-655
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• 2014

Uvala is one of the geographic features which have been discussed very actively in the field of Karst geomorphology, but most researches in Korea have been staying at the level which uvala were discussed from the viewpoint of the Karst cycle. In this study, the geomorphological characteristics of Kwangduck-ri Uvala will be identified on the basis of the various definitions, and the irrigation systems which have been developed during 250 years will be analysed using a number of data, such as interviews, statistical data, maps, air-photos, especially topographical analysis from GIS. It is concluded that the site of Kwangduck-ri Uvala would have shown the genuine history to adapt and overcome the obstacles of harsh karst environment and to make the stable agricultural and irrigation system in the high plateau karst area.

• Journal of the Korean Association of Geographic Information Studies
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• v.13 no.2
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• pp.54-63
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• 2010

The intensive rainfall over 455 mm occurred between on 9 to 14 July 2009 triggered debris flows around the mountain area in Jecheon County. We mapped the debris flow area and estimated the debris flow volume using a high resolution digital elevation model (DEM) generated respectively from terrestrial LiDAR (Light Detection And Ranging) and topographic maps. For the LiDAR measurement, the terrestrial laser scanning system RIEGL LMS-Z390i which is equipped with GPS system and high-resolution digital camera were used. After the clipping and filtering, the point data generated by LiDAR scanning were overlapped with digital map and produced DEM after debris flow. The comparison between digital map and LiDAR scanning result showed the erosion and deposition volumes of about $17,586m^3$ and $7,520m^3$, respectively. The LiDAR data allowed comprehensive investigation of the morphological features present along the sliding surface and in the deposit areas.

• Journal of the Korean association of regional geographers
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• v.21 no.3
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• pp.608-617
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• 2015

This paper synthetically analyzes micrometeorological data and geomorphological features of Doeksan-ri Eoreumgol(ice valley) Yeongdeok-gun in order to investigate occurrence characteristics of the ice valley and a mechanism for freezing in summer. This ice valley is located in the distal end of a talus and intensity of cooling and freezing in summer seems to be related to morphology and dimensions of talus. Cooling in the ice valley is generated by cold air flows that move down to the bottom of talus from high mountains through pores and voids, then debris in talus is supercooled by the cold air. For it forms a stable state in and around voids cold air is stagnating in the lower end of talus. This causes freezing in summer at outpour points. Furthermore humidity condition of external air and vaporization heat is a key factor when freezing.

• Journal of the Korean earth science society
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• v.38 no.7
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• pp.552-560
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• 2017

This study investigates the development process of Mt. Deok on Bigeum Island, Shinan, on the basis of geomorphological and geological analyses. K-Ar dating was carried out on two samples of the acidic lapilli tuff developed in the study area, and the obtained K-Ar ages are $70.4{\pm}1.4$ and $76.9{\pm}1.5Ma$, which correspond to the Late Cretaceous (Campanian). Mt. Deok is surrounded by rock cliff, and various weathering microtopographic features, such as tafoni, tor and gnamma, are developed. Tafoni with diverse morphologic types is the most dominant feature, indicative of intense salt weathering. Geological characteristics such as porous tuff and joint have played an important role in the development of tafoni and rock cliff. Geomorphology and geology of Mt. Deok reflect paleoenvironmental change and interaction between human and nature in the coastal area.

• Journal of Korean Society of Forest Science
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• v.15 no.1
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• pp.49-60
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• 1972

During the two days of August 18, 19 of 1972, there was an unusually large number of mass soil movements resulting from severe storms in northeastern Ansong-chon Watershed. The study had several conclusions in connection with relationship between mass soil movement events and certain causing factors such as geology, soil, forest types, degree and profile of slopes, and other geomorphological features. Discussed on the forms and types of the movements including its sizes. Perhaps one of the most important problems facing the Preventive Soil Conservation is to determine the extent of critical conditions of mass soil movement events. Some results of the study will be enough to contribute for interpretation of the problems in this field.