• Korean Journal of Mineralogy and Petrology
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• v.35 no.3
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• pp.235-258
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• 2022

We interpreted the evolutionary history of the southwestern part of the Pohang Basin, the largest Miocene basin in the southeastern part of the Korean Peninsula, based on the detailed geological mapping and analysis of the geological structures. The southwestern part of the Pohang Basin can be divided into the Bomun Domain in the west and Ocheon Domain in the east by an NNE-trending horst-in-graben. These two domains have different geometries and deformation histories. The Bomun Domain was rarely deformed after the incipient extension of the basin, whereas the Ocheon Domain is an area where continued and overlapped deformations occurred after the basin fill deposition. Therefore, the Bomun Domain provides critical information on the initial extension mode of the Pohang Basin. The subsidence of the Bomun Domain was led by the zigzag-shaped western border fault that consists of NNE-striking normal and NNW-striking dextral strike-slip fault segments. This border fault is connected to the Yeonil Tectonic Line (YTL), a regional dextral principal displacement zone and the westernmost limit of Miocene crustal deformation in SE Korea. Therefore, it is interpreted that the Pohang Basin was initially extended in WNW-ESE direction as a transtensional fault-termination basin resulting from the movement of NNE-striking normal and/or oblique-slip faults formed as right-stepover in the northern termination of the YTL activated since approximately 17-16.5 Ma. As a result, an NNE-trending asymmetric graben or half-graben exhibiting an westward deepening of basin depth was formed in the Bomun Domain. Afterward, crustal extension and deformation were migrated to the east, including the Ocheon Domain.

• Economic and Environmental Geology
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• v.38 no.6 s.175
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• pp.643-656
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• 2005

The East Sea, a marginal sea or back-arc basin, consists of Japan Basin, Yamato Basin, and Ulleung Basin and is surrounded by the Pacific Plate and Philippine Sea Plate. Ulleung Basin locates in the southwestern part of the East Sea and shows the depth of 1,500 m in average and 2,500 m in maximum, connecting to the Japan Basin along 2,000 m contour. The slope of the seafloor is greater in the western side of the basin than in the southern and the eastern side. The crustal thickness of the Ulleung Basin from the OBS tends to get thicker toward the north and the west side and the sediment thickness of the Ulleung Basin is getting thicker toward the southeast side and reaches up to 12 km. The crustal type of the Ulleung Basin was variously suggested as like as a rifted continental crust, an extended continental crust, and an incipient oceanic trust. The origin of the crustal formation and the Ulleung Basin, however, is still controversial. Based on the bathymetry and gravtiy anomaly data for this study, the axis of the Ulleung Basin shows that the basin develops along the axis trending NW-SE direction and reveals a general symmetry of the bathymetry. And also the free-air gravity anomalies show a very similar pattern to the bathymetry of the basin. The sediment thickness is relatively thicker in the southeastern side of the basin than in the northwestern side. Although the crustal age of the Ulleung Basin is supposed to be younger than them of the Japan Basin and the Yamato Basin, the free-air gravity anomalies of the Ulleung Basin ranging -40 to 50 mGals are lower than the other basins, which suggests that the densities of crust and sediment of the Ulleng Basin are lower than the Japan Basin and the Yamato Basin.

• Economic and Environmental Geology
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• v.39 no.2 s.177
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• pp.129-149
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• 2006

Previously published stratigraphic, sedimentologic, paleontologic, paleomagnetic and geophysical data are reviewed to make an understanding on the tectonic evolution of the Cretaceous Gyeongsang (Kyongsang) basin, southeast Korea. A stratigraphic framework and a tectonic model on the formation and deformation of the Gyeongsang Basin are newly proposed on the basis of integration these data with magmatism and mineralization ages in the basin. A newly proposed stratigraphic framework indicates that strata in the basin can be subdivided into five distinct stratigraphic units that represent pre-rifting, syn-rifting, inversion I, II, and III stages. The Gyeongsang Basin was formed initially as a pre-rifting stage due to north-south extension in the Late Jurassic prior to a syn-riftins stage that resulted from east-west extension during the Early Cretaceous. In the Late Cretaceous, the basin was deformed by three-staged sequential deformation of north-south, northwest-southeast, and east-west compressions. The tectonic history of the basin has been largely controlled by the change of motion of the Izanagi Plate from north to northwest during the Cretaceous. In the early Cretaceous, the Izanagi Plate began to subduct northward beneath the Eurasian Plate and caused the left-lateral strike-slip fault systems in the southern part of the peninsula. The left-lateral wrenching of these fault systems was causally linked to development of pull-apart basins, such as the Gyeongsang Basin in the southeastern part of the peninsula. However, northwestward movement of the Izanagi Plate during the Late Cretaceous probably led to the extensive volcanism as well as sequential deformations in the basin. The stratigraphic and tectonic model, which is newly proposed as a result of this study, may be expected to enhancing the efficiency for exploration and exploitation of useful mineral resources in the basin as well as establishing geologic history in the Cretaceous Gyeongsang Basin. Together with the spatial and temporal correlation of the Cretaceous basins in adjacent areas, this stratigraphic and tectonic model provides a new geologic paradigm to delineate the sophisticated tectonic history of East Asia turing the Cretaceous.

• Korean Journal of Medicinal Crop Science
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• v.7 no.2
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• pp.89-93
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• 1999

This study was carried out to investigate the effects of planting density, time and frequency of pinching on growth and yield of Lycium chinese Miller cultivated in vinyl house. This experiment was conducted at the experimental field of Cheong-yang Agriculture High School, Cheong-yang, Chung-nam province, in 1997 to 1998. The number of flowers, fruit setting number and dry weight of fruits per branch were increased as the spacings were wider, but the fruit yield per unit area was decreased up to the narrowest spacing plot of $60\;{\times}\;20cm$. The good results of growth status and fruit yield was obtained at the early pinching in May 5. As the more frequent pinching were treated, the more number of flowers and fruits per branch were produced, showing increase of fresh and dry yield, because of much more branches per plot.

• 한국지구물리탐사학회:학술대회논문집
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• 2005.05a
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• pp.203-208
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• 2005

We have performed magnetotelluric (MT) surveys to investigate the deep crustal structure of Gyeongsang basin. The MT data were collected in the frequency range from 0.00042 to 320Hz along a profile across the Gyeongsang basin, and 2-D inversion was carried out to interpret the geoelectrical structure. We also extracted gravity data around the MT profile from KIGAM database and calculated the density inversion to compare with the geoelectrical structure. The results obtained are good agreement with geological distribution and indicate contrasts of physical properties of sedimentary rock, igneous rock and metamorphic rock.

• Journal of the Korean Geographical Society
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• v.39 no.4
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• pp.514-527
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• 2004

We investigated the distribution and geomorphic development of alluvial fans at Cheongdo- and Hweyang-eup(town) in the Cheongdo Basin, Gyeongsangbuk-do(Province) of Korea. The alluvial fans of study area are formed confluently to the E-W direction at the northern slope of the Mt. Namsan(840 m). They are classified into Higher surface, Middle surface, and Lower surface according to a relative height to a river bed. And the older alluvial fan is, the deeper gravel in the stream deposits is weathered. The magnitude of each surface composing of confluent fans is related to that of the drainage basin. So called fan-basin system of magnitude on the study area is on the positive(+) relation in the study area. The large fans over 1km in radius are found on the basin of andesite rock which is resistant to the weathering and erosion. Moreover there is no tectonic movement in the basin. It means the most important element influenced on the fan formation is not tectonic movement, but the Quaternary climatic change, which is the periglacial climate alternating glacial and interglacial stages during the Quaternary. Therefore alluvial fans would distribute in Korea overall influenced by the Quaternary climatic change.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.2
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• pp.107-110
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• 1982

Two strains of branched wheat introduced from CIMMYT were crossed with two varieties of normal headed common wheat (Triticum aestivum L.). The number of genes conditioning branching trait in the two strains was determined from the studies of $F_1$ and $F_2$ populations under longday and shortday conditions. Branching strains PH 119 appeared to have three recessive genes and PH 127 two receive genes. The segregating ratio of branching vs normal was unaffected by the different photoperods but the expression of branching trait was little more vigorous under the shortday condition. Both PH 119 and PH 127 had a single dominant gene for glume pubescence. Association between branching trait and glume pubescence was determined with the $X^2$ -test for independence. Glume pubescence was not associated with branching in PH119 $\times$ Chugoku 81 but was associated in PH119 $\times$ Olmil (p < 0.05).

• Journal of the Korean association of regional geographers
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• v.12 no.2
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• pp.202-214
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• 2006

In this paper Gumho drainage basin is divided into six geomorphic units (Bohyeon, Palgong, Biseul mountainous areas and Yeongcheon, Gyeongsan, Daegu basin), and physical geographical background and distributional characteristics of geotourism resources in each geomorphic unit are examined. Most(32 sites, 78%) of geotourism resources in Gumho basin reflect geomorphological environment, rest(7 sites, 17%) of them reflect geological environment. There are three geomorphological resources in Bohyeon mountainous areas, eight geomorphological resources in Palgong mountainous areas, and five geomorphological resources and one cultural resource in Biseul mountainous areas. There are two geomorphological resources, one geological resource, one biological resource, and two cultural resources in Yeongcheon basin. Among them one biological resource and and one cultural resource reflect local geomorphological environment. In Gyeongsan basin are there one geomorphological resource, three geological resources, and one biological resource, but one biological resource reflects local geomorphological environment. There are eight geomorphological resources, two geological resources, and three biological resources in Daegu basin. But two biological resources among them reflect local geomorphological environment.

• Journal of The Geomorphological Association of Korea
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• v.19 no.4
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• pp.97-108
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• 2012

There exist plenty of geomorphological resources in Haean Basin, Yonghwasan Mt., and Gandong Basin in Eastern DMZ area in Gangwon Province which can be used as geotourism resources. Meticulous strategies are necessary to improve the geotourism bases in such a mountainous region. Potential geosites including Yongneup and Simjeog wetlands are nearby, so it is necessary to include these geosites when planning geotourism courses. The values of these sites coinciding with the goal of geopark are as follows: this region shows contrasting landforms derived from distinctive rocks such as gneiss and biotite granite, and there are many landforms derived from differential weathering of granite too. They can be used to explain the developmental history of numerous basin structures in entire Korean peninsula.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.3
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• pp.269-272
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• 1981

To know the characteristics of flowering in rape, flower numbers, flowering speed, flowering period, pod numbers, pod formation period, and oil content were examined by individual plant and by each of branches per plant. The results are; 1) plant had in average 1, 400 to 1, 500 flowers, 2) completion of flowering per plant took 30 days, 3) pod numbers per plant was ranged from 560 to 630, 4) plant had 18 to 20 primary branches, 5) five days were needed for pod formation, 6) no difference in flowering speed by the position of branches, 7) flowering period was shortened by 0.5 days per branch by going to upper part, 8) oil content of seeds was significantly higher on the upper and lower part than on the middle part branches.