• The Korean Journal of Quaternary Research
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• v.20 no.2
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• pp.11-29
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• 2006

A bedrock river is a channel in which bedrock is exposed along the channel bed or walls for at least approximately half of its length. In some case, a continuous alluvial veneer may be present, but this is completely mobilized during floods. From the point of long term landscape evolution during the Quaternary, the bedrock channel determines local base level and the lowering rate of bedrock channels controls the rate of erosion and transport processes and forms on the adjacent hillslopes. In this review, various erosional processes in bedrock river channels are classified and discussed. Especially, theoretical and numerical models on channel bed abrasion with bed load sediment particles are introduced and discussed.

• The Korean Journal of Quaternary Research
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• v.20 no.1 s.26
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• pp.28-38
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• 2006

Since the radioactivity of U was discovered by Becquerel in 1896, a number of radiometric dating techniques based on radioactive decay have been developed with the help of precise and accurate instruments. Among them, radiocarbon dating was introduced as the most effective method in archeology in Korea. However, though the radiocarbon methods have contributed greatly to the development of archeology in Korea, it is limited to organics in a matrix of soil and sediment, including organic carbon, charcoal, bone and so on. If there are no organics in some paleolitic sites, other methods are required for dating. Therefore, we introduced OSL (Optically Stimulated Luminescence) dating method in this paper. The method is mainly based on quartz grains or other particles. The aim of this paper is to discuss about sampling method and the limitation of its application in archeology.

• The Korean Journal of Quaternary Research
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• v.25 no.1
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• pp.31-39
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• 2011

Phytolith of soil in earthenware buried in the wooden chamber tombs at the archaeological site in Hwangseong-dong, Gyeongju along Hyeongsan River are analyzed. The study area has adjoined the seat of government during approximately thousand years in Shilla Dynasty and can be regarded as being closely related to the agricultural activities using the floodplains of Hyeongsan River. By the analytical results, Phragmites, Paniceae and Andropogoneae as well as Oryza sativa are found in the lower horizons, indicating the agricultural activities in the nearby areas. It is suggested for understanding the use of earthenware that the comparisons of buried soils in the site and soils in the earthenware and analysis on the macro plant fossils of soil in the earthenware are needed.

• The Korean Journal of Quaternary Research
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• v.25 no.1
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• pp.41-49
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• 2011

Archaeological survey has been carried out to find some evidence of human occupation in 31 caves in Pyeoungchang, Danyang, Jincheon, Goesan, Munkyoung, Boeun, Sangju in central limestone area of the Korean peninsula. Among those caves, some archaeological evidences were observed in 11 caves. Various types of potteries, animal bones and stone artifacts were collected on surface of sediments in caves. Among them, the Mosan cave in Munkyoung and the Kwangcheonseongul in Pyeoungchang are very likely to yield important archaeological remains in the well preserved deposits in the caves. Further researches are expected to provide significant information for explaining human living from prehistoric time to historical periods.

• The Korean Journal of Quaternary Research
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• v.24 no.2
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• pp.13-21
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• 2010

The Piseo-ri site in Muan provides significant data in investigation on the Paleolithic sites in the southwest coast of Korea. Stratigraphic and geological analysis indicates that the characteristic of soil wedge can vary in accordance with soil property and relief of paleo-surface. Considering that the cultural layer was deposited after the Last Glacial Maximum, co-occurrence of the late Middle to early Upper Paleolithic stone tools suggests a possibility of redeposition of different ages resulted from active erosion. The result shows that the distribution of the Paleolithic tools and the property of soil wedge could be controlled by environmental conditions such as relief of paleo-surface and climate.

• The Korean Journal of Quaternary Research
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• v.23 no.1
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• pp.42-53
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• 2009

In response to the abrupt climate change in recent years, atmosphere, ocean and cryosphere are reported to be altered. In addition to these changes, the land surface is also gradually changing and its impact on the global climate may not be negligible. The land surface change impacts the global climate via two ways, the biogeochemical and biophysical feedbacks. The biogeochemcial change in the land surface modifies the atmospheric trace-gas concentrations through a change in photo synthesis, while biophycal changes of the land surface alters the surface albedo, which influences the amount of the short wave radiative heat fluxes. There are many examples in the past that the change in land surface greatly influences the global climate change. The recent IPCC report has suggested that the climate change will occur rather abrubtly in the near future. In order to predict the future climate accurately, the impact of the land surface change is fully considered.

• Journal of The Geomorphological Association of Korea
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• v.19 no.3
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• pp.97-108
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• 2012

During the last few decades, the ever-increasing knowledge of coastal morphogenic processes has made marine terraces the most recognizable, widespread and scientifically reliable records to determine both qualitatively and quantitatively the vertical movements that have affected the tectonically active coastal regions during the Quaternary. This study first aims to address the marine terrace records from Suje-ri to Suryum-ri along the coast of Gyeongju, SE Korea. Eight distinct flights of terraces, including HH YC, elevated up to 160 m above present sea level have been mapped along the coast of the study areas, and are designated $L_{II}$ to HH YC from the youngest to oldest. Based on the elevation of paleo-shoreline and inferred formation age for HH YC uplift rate since the middle Pleistocene has been estimated at 0.23 mm/year. Establishing the nature and timing of the uplift history derived from marine terraces provide a better understanding of neotectonic framework for explain enigmatic, complex landscape evolution in the Korean peninsula.

• The Korean Journal of Quaternary Research
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• v.31 no.2
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• pp.1-12
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• 2017

A total of 23 specimens were collected from the trench sections of the archaeological area, around Yongseong-ri, Buryang-myeon, Gimje. The diatoms identified to 61 species belonging to 32 genera and species diversity and abundance were very few. Three diatom assemblage zones were set up according to the vertical assemblage of each horizons, the absolute abundance of diatoms and the distribution of indicator species. In diatom assemblage zone I, marine species was mainly occurred. Because the marine species is not reported in study of the adjacent area, it is valuable data on sea-water inflow. In diatom assemblage zone II, the yield of brackish and freshwater species are abundant, indicating that the brackish water environment was caused by the influx of freshwater. In diatom assemblage zone III, the yield of freshwater species is high and species of genus Eunotia are mainly occurred. It is considered that they are deposited in wet soil environment where freshwater inflows occasionally.

• The Korean Journal of Quaternary Research
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• v.32 no.1_2
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• pp.51-66
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• 2018

Climate change and large-scale human interference increase flow instability due to changes in watershed flow and sediment transport patterns. There are local problems in solving problems related to sediments, namely the existence of specific problems at specific sites or areas, and the resolution of these problems is limited to short-term and regional, resulting in other temporal and spatial influences and impacts. Therefore, this study intends to introduce and propose a conceptual framework for comprehensive sediment management in terms of watershed scale for solving problems related to sediments in watersheds. In the watershed scale, comprehensive sediment management should be done, to do this, a comprehensive understanding of the movements of sediments accompanied by cooperation with science-policy-operation-residents should be given priority.

• The Korean Journal of Quaternary Research
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• v.33 no.1_2
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• pp.25-35
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• 2021

In this study, we identified characteristics of heatwaves on the Korean Peninsula and related atmospheric circulation patterns using data on the daily maximum temperature (TMX) and reanalysis data for the past 42 years (1979-2020) and analyzed their connection to the Arctic oscillation (AO). The heatwave on the Korean Peninsula showed to be stronger and more frequent in the 2000s. The recent strong and frequent heatwaves on the Korean Peninsula are mainly affected by abnormal high-pressure over the Korean Peninsula on the middle/upper-level atmosphere and the strengthening of the North Pacific high pressure. Interestingly, composite difference of sea level pressure showed very similar results to the positive AO pattern. The correlation coefficients between the summertime AO and the TMX and HWD of the Korean Peninsula were 0.407 and 0.437, respectively, which showed a statistical significance in 1%, and showed a clear relationship with the abnormal high-pressure over the Korean Peninsula and the strengthening of the North Pacific high pressure. In addition, in the positive AO phase, the TMX and HWD of the Korean peninsula were approximately 30.1 ℃ and 14.6 days, which were about 1.2 ℃ and 8.8 days higher than in the negative AO phase, respectively. As a result of the 15-year moving average correlation analysis, the relationship between the heatwave and AO on the Korean Peninsula has increased significantly since 2003, and the linear relationship between them has become more apparent. Moreover, after the 2000s, when the relationship developed, AO had more strongly induced the atmospheric circulation pattern to be more favorable to the occurrence of heatwaves in the Korean Peninsula. This study implies that understanding the AO, which is the large-scale variability in the Northern Hemisphere, and the Arctic-mid latitude teleconnection, can improve the performance of global climate models and help predict the seasonality of the summer heatwave on the Korean Peninsula.