• The Korean Journal of Petroleum Geology
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• v.5 no.1_2 s.6
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• pp.27-35
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• 1997

The Gorae II area is located in the southwestern margin of the Ulleung Basin, East Sea and corresponds to the Ulleung Trough. The survey of 3D seismic data in this area was performed to delineate the structural leads confirmed by the previous 2D seismic data. As a part of 3D interpretation, basement related structural movements and their relationship with the stratigraphy were studied. The study shows that eight sequences were identified which are genetically related to the tectonics and sediment supply in this area. The geologic structures characterizing the study area consist of : (1) block faults developed in the early stage of basin opening, (2) late Miocene thrusts, and (3) Pliocene wrench faults. The eight sequences consist of pre-rift (acoustic basement), syn-rift (Sequence $A_1, A_2$), post-rift (Sequence $B_1{\~}B_3$), syn-compressional sequence (Sequence C), and post-compressional sequence(Sequence D) from oldest to youngest. The time structure and isochron maps were constructed for each sequence and also used in seismic facies analysis and interpretation of sedimentary environment. The interpretation results reveal that the relative sea level changes caused by several stages of tectonic movements and sediment supply control the stratal and structural geometry of Ulleung basin.

• Economic and Environmental Geology
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• v.50 no.2
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• pp.129-143
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• 2017

The shallow sediments in the southwestern Ulleung Basin consist of mass flow deposits such as slide/slump and debris flow deposits (DFD), caused by slope failure. These sediments are proven to be important in studying geological disaster and stability of the seafloor. In this paper, we analysised the flow accumulation and slope failure susceptibility of the Ulleung Basin on the basis of multi-beam data, collected in this area. We also studied the distribution pattern and the seismic characteristics of the DFD in the uppermost layer of the Ulleung Basin on the basis of seismic data. The slope susceptibility was calculated as the frequency ratio of each factors including slope, aspect, curvature and stream power index (SPI), which causes the slope failure. These results indicate that the slope failure is frequently to occur in the southern and western continental slope of the Ulleung Basin. The sediment flow (mass flow) caused by the slope failure converges to the north and northwest of the Ulleung Basin. According to the seismic characteristics, the uppermost layer in study area can be divided into four sedimentary unit. These sedimentary units develop from the south and southwest to the north and northwest in association with slope susceptibility and flow accumulation.

• Geophysics and Geophysical Exploration
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• v.17 no.2
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• pp.74-87
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• 2014

Analysis of multi-channel seismic reflection profiles collected from the Ulleung Basin reveals that the Quaternary sequence consists of four stratigraphic units separated by erosional unconformities. Individual stratigraphic unit includes eighteen mass transport deposits which are variable in geometric characteristics and spatial distribution. Each mass transport deposit on the seismic profile is acoustically characterized by chaotic or transparent seismic facies, and shows wedge or lens-shaped external geometry. The mass transport deposits, which comprise a succession of stacked wedges, mainly occur on the southern slope, and their thickness gradually decreases toward the basin plain. The time structure map of erosional unconformities shows that a tectonic-induced structural high and troughs toward the northwest and northeast are developed at the central part of the basin. Based on the isochron map, the mass transport deposits, originated from southern part of the study area, transported to the basin plain and can be divided into two groups by the structural high. Consequently, the mass transport deposits within the Quaternary sequence in the Ulleung Basin are largely controlled by the large amounts of sediment supply, dissociation of gas hydrate during the lowstands, and central structural high.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.6
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• pp.447-451
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• 2003

When sowing green peas in the autumn, proper seedling stands and growth quantity should be secured before winter begins. Also, for proper acclimatization, injuries caused by low temperatures, frost or high temperatures in the P.E. film during mulching, should be avoided during the regeneration period; that being early spring. The days required for growth in each stage in Yeosu are shorter than those in Naju because Yeosu has high temperatures during the growth period. Furthermore, in Yoesu, it was observed that there were more effective branches as well as effective and attached node positions on the branches. The first pods on the main stems and effective branches were observed to be higher than those in Naju. The number of pods per plant and the number of seeds per pod in Yoesu was greater than for those in Naju and the pod length was longer as well. Considering the missing plant rate, growth, and green pod yield, the optimum sowing date for the green pea was mid-November in both location. The stable acclimatizing date for the green pea was early March when the highest yield can be acquired due to a lot of effective branches and pods per plant and with the lowest missing plant rate and rate of injury in acclimatization.

• Proceedings of the Korean Information Science Society Conference
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• 2003.10b
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• pp.652-654
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• 2003

본 논문에서는 리본스네이크와 원형템플릿을 이용한 관상동맥추출 방법을 제안한다. 이 방법은 조영사진술로부터 획득된 관상동맥영상으로부터 동맥경화 유무를 쉽고 정확하게 진단하는데 필요한 혈관영역만을 추출하는 방법이다. 기존 방법에서는 혈관영역전체를 동일한 방법으로 추출하지만 본 논문에서는 혈관을 구성하는 각 세그먼트별로 적합한 추출방법을 적용한다. 즉 혈관에서 팽행선을 이루는 부분에 대해서는 항공사진 또는 위성영상에서 도로영역을 추출하는데 사용되는 리본스네이크를 적용하고 혈관의 분지부에 대해서는 원형템플릿과 혈관벽과의 교점의 개수를 분석하는 방범을 사용한다. 이때 원형템플릿의 중점과 교점들이 이루는 각도의 변화율을 고려함으로써 보다 정확한 혈관분지부를 검출할 수 있다.

• Journal of the Korean earth science society
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• v.21 no.1
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• pp.59-66
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• 2000

In Kyeongsang basin, there were very dynamic magmatic activities, resulting to form volcanic and plutonic rocks. A plutonic recycle appeared in this region. Presumption of the pressure for hornblende-bearing granitic rock among the plutonic rocks, can support important informations for the emplacement depth of Cretaceous Bulgugsa granites in Kyeongsang basin. $Al^T$(Al total) contents of hornblende is related to the pressure, oxygen fugacity, and compositions of other minerals having the solid solution. So we apply the $Al^T$ content of hornblende to several empirical and experimental geobarometer systems to presume the pressure and to determine the emplacement depth of Cretaceous Bulgugsa granites in Kyeongsang basin from the inferred pressure. With the result that we applied the $Al^T$ contents of hornblende to the various geobarometers, there was a positive relationship between the pressure and $Al^T$. The minimum pressure value ranges from 0.73 to 1.70kbar in Kyeongju and the maximum value from 2.02 to 3.16kbar in Kimhae. And then the tectonic setting in Kyeongsang basin has no relation to the emplacement depth of Cretaceous granites and means variations with the movement of vertical component in each area. As we suppose that the density of earth's crust is $2.8g/cm^3$, the average values of the emplacement depth ranges in each area range from 2.6 to 11.4km. These data confirm the previous idea about the emplacement depth of Cretaceous granites in Kyeongsang basin, and these geobarometers using the $Al^T$ contents of hornblende is available though they have much limits. Therefore Cretaceous Bulgugsa granites in Kyeongsang basin was the shallow depth intrusive rut and the exposed granites was the shallow depth crust.

• Journal of the Geological Society of Korea
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• v.54 no.6
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• pp.631-640
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• 2018

To understand the formation and evolution of a sedimentary basin in basin analysis and modelling studies, it is important to analyze the thickness and age range of sedimentary layers infilling a basin. Because the compaction effect reduces the thickness of sedimentary layers during burial, basin modelling studies typically restore the reduced thickness using the relation of porosity and depth (compaction trend). Based on the compilation plots of published compaction trends of representative sedimentary rocks (sandstone, shale and carbonate), this study estimates the compaction trend ranges with exponential curves and equations. Numerical analysis of sedimentary compaction is performed to evaluate the variation of porosity and layer thickness with depth at key curves within the compaction trend ranges. In sandstone, initial porosity lies in a narrow range and decreases steadily with increasing depth, which results in relatively constant thickness variations. For shale, the porosity variation shows two phases which are fast reduction until ~2,000 m in depth and slow reduction at deeper burial, which corresponds to the thickness variation pattern of shale layers. Carbonate compaction is characterized by widely distributed porosity values, which results in highly varying layer thickness with depth. This numerical compaction analysis presents quantitatively the characteristics of porosity and layer thickness variation of each lithology, which influence on layer thickness reconstruction, subsidence and thermal effect analyses to understand the basin formation and evolution. This work demonstrates that the compaction trend is an important factor in basin modelling and underlines the need for appropriate application of porosity data to produce accurate analysis outcomes.

• Weed & Turfgrass Science
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• v.2 no.1
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• pp.88-94
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• 2013

Brown patch caused by Rhizoctonia solani AG-1 IB occurred on Kentucky bluegrass during late May through early October 2010 at golf course in Gyeongbuk Province, Korea. Disease symptoms on the turfgrass for spring season were leaf blights dying from the leaf tip, which appeared patches of brown color in the field. However, it appeared patches of dark brown color or gray brown color in fall. The fungus (B-7 isolate) of brown patch was isolated from the diseased leaf tissue and cultured on potato-dextrose agar (PDA) for identification. The young hyphae had acute angular branching and few septa and mature hyphal branches showed about 90-degree angles and development of monilioid cells, which were morphologically identical to Rhizoctonia solani AG-1 IB reported previously. DNA sequences of ribosomal RNA gene (internal transcribed spacer) of the fungus were homologous with similarity of 99% to those of Rhizoctonia solani AG-1 IB isolates in GenBank database, confirming the identity of the causal agent of the disease. Pathogenicity of the fungus was also confirmed on the creeping bentgrass and Kentucky bluegrass by Koch's postulates. This is the first report of brown patch on Kentucky bluegrass caused by Rhizoctonia solani AG-1 IB in Korea.

• Horticultural Science & Technology
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• v.32 no.4
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• pp.571-575
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• 2014

'Dream Song' is a cultivar of Gypsophila paniculata developed by the Jeollabuk-do Agricultural Research & Extension Services in 2010 for cut-flower production. This hybrid was bred from 121 seedlings collected from an open-pollinated population of 'Gyp06-11'. It has novel morphological characteristics of upright plant type, lanceolate leaves, double florets with a few bright white-colored petals of obovate shape, truncate petal tips, and cup-shaped calyces. Furthermore 'Dream Song' has desirable cultivation characteristics including narrow branching angle, and moderate resistance to powdery mildew, thrips and leaf miners. Moreover it produces more primary branches, and longer internodes and flower stalks than reference cultivar 'Bristol Fairy' during summer cultivation in a subalpine area (500 m over the sea level). Flowering in 'Dream Song' is delayed by about 17 days as compared to 'Bristol Fairy'. 'Dream Song' produces normal flowers with 2 pistils and an average of 10.4 stamens, with fewer malformed flowers than 'Bristol Fairy'.

• Journal of the Korean earth science society
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• v.43 no.3
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• pp.405-429
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• 2022

Detrital zircon LA-MC-ICP-MS U-Pb dating of the Cretaceous Gurye Group, Gurye Basin, was carried out. Gurye Group consists of Supyeongri, Geumjeongri, Togeum, and Obongsan formations in ascending order, and five samples were collected for age dating. Based on the dating results, the lowermost Supyeongri and the uppermost Obongsan formations show narrow age ranges. Only Precambrian and Late Cretaceous zircons were found in the Supyeongri and Obongsan formations, respectively. However, the upper and lower Geumjeongri, and Togeum formations show wide age ranges from the Precambrian to Cretaceous. The youngest detrital zircon U-Pb ages of each formation except the Supyeongri Formation, which lacks Cretaceous zircon, were calculated to be ca. 107.4 Ma in the lower Geumjeongri Formation, ca. 104.6 Ma in the upper Geumjeongri Formation, ca. 97.7 Ma in the Togeum Formation, and ca. 88.5 Ma in the Obongsan Formation. Such results indicate that the depositional age of the Gurye Group can be constrained from the Lower Cretaceous Albian to the Upper Cretaceous Coniacian. Based on the distribution of the detrital zircon ages from each formation, the source area of the Gurye Group is interpreted to have been extended from the adjacent Youngnam Massif to the Okcheon Belt throughout the basin evolution. The increase of the Cretaceous zircon with time is thought to reflect the slab roll-back of the proto-Pacific plate during the Cretaceous.