• Journal of The Geomorphological Association of Korea
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• v.24 no.2
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• pp.1-13
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• 2017

Massive coastal sand dunes are distributed in Ui-island, Shinan-gun. The sand dunes in Ui-island is worth studying, in terms of preserving natural environment without anthropogenic impacts. In this study, we surveyed geomorphological processes of the sand dune based upon measuring of geometric properties, grain size analysis, and OSL(Optically Stimulated Luminescence) age dating. The sediments of the dune consist mainly of well sorted medium sand with about 250$\mu$m. Based on spatial distribution of sand dunes, we found that they are formed by northwest monsoon during winter, and sands are supplied from Seongchon area in northern UI-island. According to OSL age dating, the sand dunes were deposited from $0.07{\pm}0.01ka$ to $0.17{\pm}0.04ka$. This result shows that the transformation of the dune due to the sand movement by wind was active during the last 100-200 years. The aerial photograph indicates that the dimension of the largest sand dune has decreased since 1945. Further research is needed to get more detailed information on geomorphic changes of sand dunes in UI-island.

• Journal of The Geomorphological Association of Korea
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• v.24 no.3
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• pp.133-147
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• 2017

This study investigated the cases of relative location, especially focused on the geomorphological situation, for the conceptualization of the location knowledge. In order to perform this study, first of all, I approached meaning of location. In this study I used the terms 'site' and 'situation'. 'Site' as used here means the location of a given place with its local internal features or resources. 'Situation' refers to the location of place as related to other places. As to location, no place exists in isolation. Therefore, it is necessary to look beyond the internal nature of the area itself to perceive its external relations with other areas. The examples of geomorphological situation were focused on the scale linkage of the examples, the interaction between elements of earth surface processes, and the method of comparative region. The regions of examples were the landscape of Mt. Hymalaya to Bengal deep sea fan, the climatical difference of continental east and west, the landscape of Mt. Geum & Sangju beach, the landscape of the south and north face of Mt. Mai., Hamjibaakgol asymmetrical valley, and the landscape of inland sea and outer sea type island.

• Journal of the Korean Geographical Society
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• v.39 no.4
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• pp.495-513
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• 2004

The shape of land surface work as a cradle for various environmental processes and human activities. As spatially distributed process modelings become increasing important in current research communities, a classification system that delineates land surface into characteristic geomorphological units is a pre-requisite for sustainable land use planning and management. Existing classification systems are either morphometric or generic, which have limitations to characterize continuous ecological processes over the landscape. A new classification system was developed to delineate the land surface into different geomorphological units from Digital Elevation Models(DEMs). This model assumes that there are pedo-geomorphological units in which distinct sets of hydrological, pedological, and consequent ecological processes occur. The classification system first divides the whole landsurface into eight soil-landscape units. Possible energy and material nows over the land surface were interpreted using a continuity equation of mass flow along the hillslope, and subsequently implemented in terrain analysis procedures. The developed models were tested at a 12$\textrm{km}^2$ area in Yangpyeong-gun, Kyeongi-do, Korea. The method proposed effectively delineates land surface into distinct pedo-geomorphological units, which identify the geomorphological characteristics over a large area at a low cost. The delineated landscape units mal provide a basic information for natural resource survey and environmental modeling practices.

• Journal of The Geomorphological Association of Korea
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• v.27 no.1
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• pp.103-115
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• 2020

This study has analyzed and revised the geomorphological terms in the Reference Guide for Geography Textbook Compilation issued by the Ministry of Education in 2017. The current geography glossary is composed of 1,150 terms of which 24.4 percent are geomorphological one. They also amount to 52.2 percent of the terms registered in the physical geography glossary. The number of terms in coastal landforms is the maximum of fifty-eight, while the one in weathering landforms is the minimum of six. This suggests a large difference in the number of terms among landform types originating from varying geomorphic processes. A lot of ordinary words are included in the geomorphology glossary. Since they have been already registered in the Korean Standards Dictionary which is another reference guide for textbook compilation, it is appropriate to delete them out of the geomorphological terms. The geomorphology glossary also contains difficult terms written in Chinese characters, inappropriate terms and even incorrect terms which are likely to lead to misconception on landforms. The revised glossary consists of 284 geomorphological terms in which 101 terms are newly added after taking all the problems into consideration.

• Journal of The Geomorphological Association of Korea
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• v.28 no.1
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• pp.67-81
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• 2021

Geomorphological development and distribution at the macro scale provide a clue to the geotectonic characteristics that have affected the geomorphological system. This is because the developmental characteristics and distribution of the landform at the macro scale remain spatial characteristics due to tectonic processes, such as fault activity. From the perspective of tectonic geomorphology, this study identified the developmental characteristics and distribution of the Quaternary landforms in central-southern Yangsan fault and discussed its relevance to fault activity. In this paper, we presented examples and results of morphotectonic analysis of the Yangsan fault, and will present the results of age dating, stratigraphic relationship of the Quaternary landforms, and calculation of cumulative slip rate in the next paper.

• Journal of The Geomorphological Association of Korea
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• v.18 no.3
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• pp.121-129
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• 2011

This work is to elucidate in typological aspect main geomorphological processes in the morphogenetic system of Mongolian steppe zone. Its morphogenesis manifest interaction of intense gelifraction and active erosion either by slope run-off or by wind. Intense gelifraction owes both to cold temperature regime with great amplitude, and to moisture associated with snow fall. Erosion of material produced by gelifraction is assured by surface run-off of summer rainfall and spring eolian activities. The geomorphological landscape sculptured by such morphogenetic processes manifest low-relief smooth slopes. This feature reveals that intense gelifraction keeps abreast with removal of weathering product by surface run-off and wind.

• Journal of the Korean Geographical Society
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• v.48 no.2
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• pp.204-217
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• 2013

This study shows the geomorphological processes of Yuga alluvial fan at Dalseong-gun, Daegu in Korea, based on characteristics of geomorphological surfaces, analysis of geomorphological deposits and OSL age dating. Alluvial fans of this area are classified into three surfaces(YG-F1, YG-F2, YG-F3) and were formed by the depositional processes resulting from the changes in hydraulic geometry of flowing water which was a stream flowing out of mountains debouched on to a plain, not by a sudden decrease in surface gradient of river bed. YG-F3 surface, about 110,000 yr B.P.(MIS 5.4), was formed as Yongri river deposited a lot of debris. This result was due to the process that the deposition took place actively with the upward of base level as the last interglacial period began. Later, the denudation of the river valley and geomorphological surface constantly occurred and the local and seasonal changes were found in precipitation and stream discharge with the beginning of the interstadial of the last glacial stages(MIS 3), leading to YG-F2 formed by debris flow, earth flow, mud flow and stream flow. Then, short-term climate changes and temporal climate events repeatedly caused aggradation and denudation over time and going through these processes, YG-F1 is believed to have been made by earth flow or mudflow during the last glacial maximum(MIS 2).

• Journal of The Geomorphological Association of Korea
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• v.26 no.3
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• pp.69-85
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• 2019

Humans have been important driver to reconfigure the terrestrial surface of the Earth by altering its morphology and processes. The effect of human activities on the physical landscape, however, shows substantially uneven geographical patterns. Most of anthrogemorphoogical studies regarding human-induced denudation have focused on areas with a long history of human modifications such as humid landscapes, so the hypothesis is naturally a great human impact on landscapes. The effect of human activities on dryland Earth surfaces are far less commonly studied, although erosion is one of major concerns in arid and semi-arid region regarding land and water quality degradation. The urban metropolis of Phoenix, Arizona, USA provides an opportunity to explore the impact of the Anthropocene. The Phoenix metropolitan area rests on classic desert landforms, such as extensive pediments, alluvial fans and sand sheets. Human activities including cattle crazing, wildfire resulting from introduced grass species by human, and recent urbanization processes have impacted these classic desert landforms and altered geomorphic processes. The purpose of this paper, therefore, rests in examining Anthropocene in the geomorphology of the north-central Sonoran Desert. The objectives of this paper are: i) to understand the impact of the Anthropocene on the geomorphological processes and forms through field observations; ii) to quantify the magnitude of human impacts on landscape using a published two-decade long record of erosion dataset and natural background erosion dataset in submitted manuscript at the sprawling edge of the Phoenix metropolitan region; iii) to examine how geomorphic outcome can affect the sustainability of cities through the estimation of sediment yield under the condition of urban sprawl.

• Journal of The Geomorphological Association of Korea
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• v.23 no.3
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• pp.93-104
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• 2016

High school textbooks of world geography show geomorphic featuresin arid environments such as sand dune, yardang and ventifact which are largely created by aeolian processes. Desert pavements, ubiquitous armored surfaces composed of a mosaic of clasts in hot and arid regions, are introduced as a major landform which can be attributed to wind erosion. However, they are formed by a variety of processes including deflation, surface runoff, upward clast migration and dust accretion that cause coarse particles concentration at the surface. The deflation by wind leaving a lag of coarse clasts has been solely regarded at home, even though the classical mechanism of deflation has been evaluated as a relatively unimportant process of pavement formation abroad through empiricalstudies. The accretionary model is gaining wider acceptance, thus implying that desert pavements could be formed through deposition of aeolian material. In addition, sheetflood and upward migration of clasts, irrelevant to the aeolian processes, could also create stone pavements. As a consequence, the deflation process in high school textbooks has to be urgently modified into a range of processes including aeolian mantling. By stressing that desert pavements are an exceptional geomorphic feature in deserts where wind is a predominant geomorphic agent, they can be used as a good example to demonstrate that a landform is not monogenetic.

• Journal of The Geomorphological Association of Korea
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• v.23 no.1
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• pp.35-45
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• 2016

Aiming to elucidate the formation processes of Myeonsan wetland around the ridge from Myeonsan peak to Seokgae pass, this paper analyzes the geomorphic, physical and chemical characteristics of the wetland. The results are as follow: Firstly, resistant bedrock and big boulders distributed on the riverbed of the small channel from the wetland to Seokgaecheon have played a role as a temporary base level. At the upstream part above this point, a wide and shallow depression was formed and developed into a wetland. There was a gorge covered with boulders at downstream part. Secondly, owing to the obstacles at the outlet of wetland, deposits on bed tend to be downstream coarsening. Finally, deposits show weak acidity of pH 5.0~5.7. The source of wetland water is groundwater containing rich Ca and Na. Trees in the wetland help much more Ca accumulated. And deposit biotite and amphibole contained rich Mg have been weathered in the wetland.