• Journal of The Geomorphological Association of Korea
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• v.26 no.4
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• pp.81-96
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• 2019

The Yeongdeok 53m marine terrace (Y₅₃mT), Y₄₃mT, Y₃₃mT, Y₂₄mT, Y₁₉mT and Y₁₁mT distributed along the Yeongdeok coast, southeastern Korean Peninsula are well compared with the thalassostatic terraces of the high terrace 1 (ℓHT₁ ; 51m of the relative heights from the river floor), high terrace 2 (ℓHT₂ ; 43m), middle terrace 1 (ℓMT₁ ; 32m), middle terrace 2 (ℓMT₂ ; 25m), lower terrace 1 (ℓLT₁ ; 18m) and lower terrace 2 (ℓLT₂ ; 10m) respectively, developed along the lower reaches of the Chucksan-cheon and Obo-cheon rivers, judging from the comparison of paleosols (red soils) between the above marine and thalassostatic terraces. Using the Y₁₉mT of the MIS 5e as the key surface, we propose that the terraces of the Y₅₃mT and ℓHT₁, Y₄₃mT and ℓHT₂, T₃₃mT and ℓMT₁, Y₂₄mT and ℓMT₂, Y₁₉mT and ℓLT₁, and Y₁₁mT and ℓLT₂ have been formed at the MIS 11, 9, 7e and 7a (or 7a), 5e and 5a respectively. The red soils have been developed at the Y₁₉mT and ℓLT₁ and above them, but not on the Y₁₁mT and ℓLT₂ surfaces.

• Journal of the Korean association of regional geographers
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• v.19 no.4
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• pp.627-640
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• 2013

Cette $\acute{e}$tude a pour objet d'analyser le processus de morphogen$\grave{e}$se de l'$\hat{I}$le rocheuse de Baek. Nous y voyons une cl$\acute{e}$ pour apprendre son relief marin et le processus de morphogen$\grave{e}$se des l'$\hat{I}$les m$\acute{e}$ridionales de Cor$\acute{e}$e du Sud. Le granit porphorique qui compose l'$\hat{I}$le rocheuse de Baek est une roche magmatique qui s'est form$\acute{e}$e il y a 60 million d'ann$\acute{e}$es. La cause principale de formation de l'$\hat{I}$le rocheuse de Baek, est une ligne de d$\acute{e}$lit vers le NE-SO et l'ENE-OSO, un soul$\grave{e}$vement de la plaque tectonique et une $\acute{e}$rosion par les vagues. L'$\hat{I}$le rocheuse de Baek pr$\acute{e}$sente un caract$\grave{e}$re d'$\acute{e}$ruption de magma de calc-alcalin par analyse g$\acute{e}$ochimique de son granit porphorique et fait partie du granit de l'arc volcanique. Il s'agit d'un magma qui s'est form$\acute{e}$ dans la subduction pr$\grave{e}$s du continent. Il est aussi n$\acute{e}$ssaire d'examiner un soul$\grave{e}$vement qui est plus $\acute{e}$lev$\acute{e}$ qu' un mouvement ascendant de la surface de la mer $\grave{a}$ l'$\grave{e}$re quaternaire environ de l'$\hat{I}$le rocheuse de Baek malgr$\acute{e}$ que, selon nous, nous y trouvions une faille et une terrasse marine.

• Journal of the Korean Geographical Society
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• v.30 no.2
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• pp.103-119
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• 1995

This Paper aims to compare the lower marine terraces distributed from Muckho to Gangneung in the mid-eastern coast of Korean peninsula by the geomorphic method of using characteristies of terrace features and terrace deposits, paleosol, and fossil cryogenic structures, and to estimate the age of the lower marine terraces on the basis of the comparisons of those with the characteristics of thalassostatic terrace in adjacent rivers. The 1ower marine terraces in this area can be classified into two levels, i.e., lower marine terrace I and II surfaces, in desending order, according to the difference of former shoreline altitude. The former shoreline heights of the lowerm marine terrace I and II surfaces are 18m and 10m, respectiveiy. The width of the I surface is broader and distributed more continuousiy than that of II surface. Daejin I surface in Muckho coast, and Myeongju and Anin terrace in Gangneung coast could be classified into the lower marine terrace I surface, and Daejin II surfaCe into II surface. The Surface of ancient shore platform of the lower marine terrace I and II surfaces were weathered, and the color of the terrace deposit ranges from red to reddish brown. And this terrace deposit is covered with slope deposit of Last Glacial or fossil periglacial structures (platy structure and vecicle) of Last Glacial are formed in terrace deposit. These facts indicate that the lower marine terrace I and II surfaces had been formed before the Last Glacial, and then affected by chemical weathering under warm environment, finally followed by cold period. But the deposit of the lower marine terrace I surface is more weathered than that of II surface. And pseudogleyed red soil, which is developed in I but not in II surface, could be judged to have been formed in the Last Interglacial culmination stage (Oxygen isotope stage 5e). Therefore, in terms of the degree of weathering of the terrace deposit and the existence of pseudogleyed red soil, the age of both terrace is thought to be a little different. And the characteristics of the above mentioned II surface are accord with those of thalassostatic terrace formed in middle or late period of the Last Interglacial (5e or 5a). Thus on the basis of above all points, the lower marine terrace I and II surfaces in this area could be seen to have formed in the Last Interglacial culmination stage and middle or late period of the Last Interglacial, respectively. Because the lower mamine terrace I surface is broadry distributed in the eastern coast of Korea nPeninsula, the surface could be used to be a key surface in studying Quaternary marine terraces.

• Journal of the Korean Geographical Society
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• v.44 no.1
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• pp.31-55
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• 2009

This research aims 1) to characterize the spatial distribution of low relief landforms (plains) via analyses of a Digital Elevation Model (DEM), 2) to classify plains according to morphological and genetic similarity, and 3) to develop a model to explain forming processes of plains in the Korean peninsula. Plains can easily be separated from high relief mountaneous areas by analyzing the DEM. The overall morphological and locational characteristics of plains can be categorized into lava plains, fluvial-marine plains, erosional plains, intermontane basins, and higher ground plains. It is concluded that the characteristic of each plain type is decided by base-level changes caused by tectonic uplift and sea-level changes, and topological relationship of different rock types. Different plain types do not exist independently, but connected with each others along stream networks. The model developed is able to combine the morphological characteristics of plains with the channel network to conceptualize characteristics and development pathways of plains in the Korean Peninsula.

• Journal of The Geomorphological Association of Korea
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• v.26 no.4
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• pp.67-79
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• 2019

This study documents the level of paleo-shoreline and the timing of formation of the lowest marine terrace (1st terrace) distributed in Dadaepo, Busan, South Korea. In the study area, the elevation of paleo-shoreline of the 1st terrace is clearly identified as 5 meters above mean high tide based on the elevation of wave-cut platforms and the elevation of boundary between marine and terrestial sediments. This is well consistent with the fact that are found along the Southern coast of the Korean Peninsula including Daepo-dong, Sacheon-si. The timing of formation of the 1st terrace in Dadaepo is confirmed to have been deposited around 70,000~80,000 years BP (MIS 5a) according to OSL and IRSL dating ages. However, because the formation age of the 1st terrace in Sacheon-si Daepo-dong (Southerm coast) and Pohang-si Umok-ri (Eastern coast) previously identified as about 90,000~100,000 years BP (MIS 5c), further discussion of what is needed. Possibly, it can be interpreted that the sub-interglacial (MIS 5a and 5c) sea-level records during the last interglacial period are likely to be selective on land depending on regions.

• Journal of the Korean Geographical Society
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• v.35 no.1
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• pp.17-38
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• 2000

The marine terraces often offer come important clues to understand the topographic development during the Quaternary and the present landforms in korea. We examined the mechanism of the marine terraces formation along the coast from Samjung-Ri(community), Guryongpo-Eup(county) to Haseo-Ri, Yangnam-Myun(county), Gyungju-Si(city). Among the various but unique factors of the given coastal environment, which should contribute to the marine terraces formation together, we focused on five possible factors for the present stydy. Geologic difference in bedrocks, protrusion degree of coastiline, topological relief of sea-bottom, fluvial characteristics on land, and pattern of the waves appeared to act cooperatibely on the terrace formation of Southeastem coast in korea, while the fluvial characteristics seemed play a significant but localized role in it. Wide distribution of middle surfaces on the coast of Samjungri-Janggilri could be due to the concentration of the high waves and the weakness of the Tertiary volcanic rocks. For the sporadic distribution of the terraces on the coast of Gupungri-Gyewonri, it seemed attributable to the erosion -susceptible weak bedrock, the coastline of inner bay, shallow sea-bottom with the gentle relief, and other fluvial characteristics with the low divides. Together with the geologic difference in bedrock, other factors including protrusion degree of coast, topological relief of sea-bottom, and the transportation loads by the stream Daejongchon are believed to act cooperatively on the mechanism of the marine terraces formation on the coast of Duwonri-Upchonri.

• Journal of The Geomorphological Association of Korea
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• v.26 no.2
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• pp.55-67
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• 2019

This study tries to reveal and compare uplift rates in the southern coast of the Korean Peninsula, based on absolute ages from coastal terrace on the coast. The uplift rate in the East Coast from previous study ranges from 0.258 to 0.357 m/ka with a median rate of 0.262 m/ka and shows an increase trend from north to south. Median uplift rate of 0.082 m/ka with minimum and maximum rates of 0.053 m/ka and 0.127 m/ka, respectively, is calculated in the South Coast from previous and this studies. The uplift rate in the West Coast from 3 absolute ages in this study is 0.082~0.112 m/ka with a median rate of 0.090 m/ka. Based on these uplift rates in the southern coast of the Korean Peninsula, it can be concluded that since MIS 5, the East Coast has experienced 3 to 4 times faster uplift rate than the West and South Coasts. However, this study suggests that more discussion on whether these uplift rates are long-term tectonic movement associated with tilted warping movement since the Tertiary or short-term tectonic movement associated with isostatic rebound due to sea level change since the Last Interglacial is needed.

• Journal of The Geomorphological Association of Korea
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• v.23 no.2
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• pp.47-59
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• 2016

The formation age and depositional environment of the marine terrace I of the estimated paleoshoreline altitude of 18m in Sanhari of Ulsan coast, southeastern Korea were investigated on the basis of examination of lithofacies and stratigraphy of terrace deposits. Marine deposits of the terrace is composed of rounded boulders(70cm in diameter) and rounded pebbles(1.0cm in diameter) which overlay them. The above rounded boulders which lie on the paleo-shore platform are considered to have been formed by wave abrasion in the same period that the paleo-shore platform was developed. The rounded pebbles which lie on the rounded boulder layer are considered to have been deposited in gravel beach and berm environment, judging from the laminae developed in this layer. The paleo-shore platform and marine rounded gravel layer of the terrace are assumed to have been formed in the large transgression period of the Last Interglacial culmination stage(MIS 5e), judging from the comparision of the formation age of 125ka B.P. of Juckcheon terrace I in the adjacent Pohang coast which was dated by amino acid dating. The terrestrial deposit of this terrace was largely composed of angular and subangular gravel mixed with marine rounded pebble which has been carried away mainly from the deposit of previous marine terraces and redeposited in this terrace. The lowest peat layer of terrastrial deposit was considered to have been deposited during the period from the late MIS 5e which is the estimated finishing time of deposition of the above marine gravels to the early stage of following regression period(MIS 5d) in which the sea level was still high. The sediments of angular and subangular gravel deposit which lie on this peat layer were assumed to have been deposited during the period from the early stage of the first regression period(MIS 5d) of the Last Interglacial to the Last Glacial. The lower part of the angular gravel layer is composed of the deposits of the fluvial and colluvial sediments, whereas most of the upper and middle part of the layer is mainly composed of angular gravels of colluvial sediments formed in the cold environment.

• Korean Journal of Soil Science and Fertilizer
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• v.18 no.2
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• pp.177-188
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• 1985

To clarify the characteristics and genesis of clayey terrace soils in Yeongnam area, macro-morphological features and soil profile development indexes were investigated with the sequential soils in Yeongcheon (inland region) and in Yeongil (coastal region). The results are summarized as follows; 1. According to the physiogaphy and landuse, the terrace soils were discernible to well drained yellowish red (5 YR) profile of higher terrace (Bancheon series), moderately well drained reddish yellow (7.5 YR) profile of middle terraces (Upyeong and Hwadong series), and lower terraces (Deogpyeong and Geugrag series) which were moderately well to imperfectly drained by paddy-fication. 2. The roundness and sphericity of the gravels contained in the terrace deposits were ranged around 0.543-0.546 and 0.723-0.722, respectively. The rounded to well rounded gravels were resemble to typical alluvial origins. 3. The amount of clay minerals formed in the soil horizons per 100g of parent materials were 50.8-30.7g while the rates of the clay leached were 30.1-7.4%, and the higher terrace had the more leaching rates. 4. The index of profile development of the terrace soils ranged from 37.95 to 22.01 and the index were positively correlated with relative elevations of the soils. The rates of clay leaching were positively correlated with the ratios of clay in the illuvial horizons to elluvial horizons. 5. A similarity was observed among cumulative grain size curves of the terrace soils, but the patterns of recalculated silt free cumulative grain size curve of terrace deposits in Upyeong soils in Yeongil area were abruptly different from down layer that suggest the soil to have bisequum profile.

• Journal of the Korean association of regional geographers
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• v.9 no.2
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• pp.203-216
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• 2003

The process of constructing coastal digital elevation model(DEM), for the 3 dimensional analysis, is composed by abstracting land layers for land elevation and water depth, reprojecting UTM, relocating geographical grid, and interpolating works. The geomorphic set of shallow sea, including tidal current, tidal zone deposition, and water depth distribution, was analyzed by eye search of Landsat TM image, masking of land zone, band combination and regression analysis. Some horizontal differences, between combined DEM and surveyed data of shallow sea, was corrected for analysis. Analyzed geomorphic elements are stream channel, alluvial fan, coastal terrace, tidal current. and shallow sea bank. Results of analysis present that transported fluvial materials influence tidal sedimentation, especially from Gahwacheon river, for the role of artificial draining flooding waters from Jinyang Reservoir, almost in the summer season. In the coastal area with less tidal current, more fine materials are deposited. The influence of currental deposition are higher on small pockets with west coast of well developed terraces. The lower skirt of alluvial fans developed into the tidal zone of shallow sea. Small pocket type bays are closed by coastal current, and less influenced from tidal deposition. The bank of Jinju Bay are developed originally from submerging of remnant erosional mountain ranges, and play on the role of trapping fine materials.