• Journal of the Korean earth science society
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• v.44 no.4
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• pp.275-290
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• 2023

Structural inversion refers to the reverse reactivation of extensional faults that influence basin shortening accommodated by contractional faults or folds. On the Korean peninsula, Miocene inversion structures have been found, but the Cretaceous rocks on Geoje Island may have undergone inversion as early as the Upper Cretaceous. To evaluate the structural inversion on Geoje Island, located on the eastern side of South Korea, and to determine the effects of preexisting weakness zones, field-based geometric and kinematic analyses of faults were performed. The lithology of Geoje Island is dominated by hornfelsified shale, siltstone, and sandstone in the Upper-Cretaceous Seongpori formation. NE and NW-oblique normal faults, conjugate strike-slip (NW-sinistral transpressional and E-W-dextral transtensional) faults, and NE-dextral transpressional faults are the most prominent structural features in Geoje Island. Structural inversion on Geoje Island was evidenced by the sinistral and dextral transpressional reactivation of the NW and NE-trending oblique normal faults respectively, under WNW-ESE/NW-SE compression, which was the orientation of the compressive stress during the Late Cretaceous to Early Cenozoic.

• Parasites, Hosts and Diseases
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• v.41 no.1
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• pp.75-77
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• 2003

The status of Pinworm (Enterobius vermicularis) egg positive rate of Primary school children in Geoje island was investigated by using adhesive cellotape anal swap method, in September, 2002. Total egg positive rates of E. vermicularis were 9.8% (74/754) and those of male and female were 10.8% and 8.7%, respectively. Among three schools examined, Myeongsa primary school showed the highest egg positive rate (12.6%) followed by Yeoncho [9.8% (26/266)] and Geoje［9.1% (35/385)]. As for the age groups, the 2nd grade had the highest egg positive rate (15.3%), whereas the 5th grade showed the lowest egg positive rate (2.6%). The above result led us to confirm that the egg positive rates of E. vermicularis in primary school children in Geoje island were not significantly different from the those in the whole country including urban and rural areas, showing more than 10%.

• The Journal of Engineering Geology
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• v.31 no.3
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• pp.239-255
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• 2021

Kinematic analyses of magmatic intrusions and faults can provide useful information on stress conditions and chronological relationships between dike emplacement and brittle deformation events. We studied structures in rocks exposed on a coastal platform in Geoje Island off the southern Korean Peninsula because of its well-developed dikes and faults. The geology of the study area includes the Cretaceous Seongpo-ri Formation, which is composed mostly of shale, sandstone, and hornfels intruded by magmatic dikes. Most of the dikes are developed along pre-existing structural features (faults and fractures), indicating that their emplacements were structurally controlled. Because dikes commonly open along the direction of the minimum principal stress, the direction of this stress can be obtained from dike geometry and orientation through the matching of piercing points on either side of a dike. In addition, the deformed dikes can give information regarding later deformation. On the basis of the kinematic analyses, we identified five deformation events in the study area, which are kinematically related to changes of the regional maximum principal stress. Results indicate that the structures in the study area have been controlled predominantly by episodes of reactivation of the NNE-trending Yangsan strike-slip fault, located to the northeast of the study area, under different stress regimes. In a wider tectonic context, the brittle deformation of the rocks of Geoje Island was probably induced by interactions among the Philippine Sea, Pacific, and Eurasian plates, including changes in subduction parameters with respect to the latter two plates over time.

• Ocean Science Journal
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• v.42 no.1
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• pp.31-39
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• 2007

Distributional characteristics of dinoflagellate cysts in surface sediments were investigated in relation to environmental factors in the eastern part of Geoje Island, Korea. Samples were collected from 10 stations in February of 2004 and water temperature and salinity were measured in February, May, September and November of 2004. Total 30 taxa of dinoflagellate cysts were identified representing 19 genera, 28 species and 2 unidentified species. Among these dinoflagellate cysts, Brigantedinium spp. of which relative proportion in th e total dinoflagellate cysts was 23.5%, was the most abundant at all stations except St. 1, and was followed by Spiniferites bulloideus (8.6%), Lingulodinium machaerophorum (8.2%) and Diplopsalis lenticula (6.7%). In addition, ellipsoidal cysts of the genus Alexandrium (Alexandrium catenella - tamarense type) and Gymnodinium catenatum, known to be causative organisms for PSP, occurred with high concentrations. Scrippsiella trochoidea was also found; however, its cyst concentration was low. Generally, species composition in the study area was similar to these reported from Jinhae Bay and Busan Harbor and several dinoflagellate cysts reflected the eutrophic condition. Cyst distribution in th e eastern part of Geoje Island seems to be influenced by the Tsushima Warm Current flowing from the southwest. The mean water temperature was $12.0^{\circ}C$ in February, $14.7^{\circ}C$ in May, $20.9^{\circ}C$ in September and $17.2^{\circ}C$ in November, which was most favorable for Alexandrium spp. growth. The abundances of dinoflagellate cysts rang e d from 528 to 2,834 cysts/g dry sediment. Higher concentrations were recognized in sediments of west area of the Jisimdo than at other stations. The cyst composition of this area was closely related to these of Jinhae Bay and Busan Harbor from which currents flow into this area. Higher cyst concentration in the west area of Jisimdo might be due to formation of the gyre.

• The Journal of Engineering Geology
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• v.5 no.2
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• pp.139-153
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• 1995

Engineering characteristics of granitic rock masses in Geoje island were estimated by investigating the mechanical and hydraulic properties of core samples drilled in - situ. Since the effect of in -situ stresses could not be considered, some of the engineering properties estimated through rock mass classification were quite different from the in - situ tested results. Based on the results of rock mass classification, borehole tests, and laboratory test the empirical parameters for the design of underground structure were assessed. Though some number of fractured zones were found, granitic rock mass in the southern part of Geoje island showed fairly good quality and the excavating conditions were expected to be suitable for the construction of large scale underground facilities.

• Korean Journal of Ichthyology
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• v.35 no.3
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• pp.189-193
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• 2023

Two specimens of Omobranchus fasciolatoceps (33.8~46.7 mm SL) were collected from oyster reefs of Osu-ri, Geoje-myeon, Geoje-si, Gyeongsangnam-do, Korea. This species is characterized by having 32~34 dorsal fin rays, 24~25 anal fin rays, 13 pectoral fin rays, 2 interorbital pores, 8 circumorbital pores, 5~7 lateral line tubes, fleshy crest on head and sexual dimorphism in female that have lost the posterior canines in both jaw. We propose the new Korean name, "Ppul-be-do-ra-chi", for the species.

• Journal of the Korean association of regional geographers
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• v.11 no.5
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• pp.368-382
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• 2005

This paper deals with the village names in Geoje City[Geoje Island], Hundreds of village names in the city are found to be based on some environmental features such as landforms, weather, and soil of the island. A considerable number of village names in the city are derived from the mountainous landforms with steep slopes or from the extremely indented coastlines with many small islands, and some village names are originated from the weather and soil. In this paper, it is realized that the village names often reflect the environments perception of the residents and that they can give some clues to the environment's changes of the places.

• Journal of the Korean association of regional geographers
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• v.3 no.2
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• pp.19-35
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• 1997

The purpose of this study is to find out the characteristics of landform in Geoje-Do using GIS and DTED data. The characteristics of landform in Geoje-Do are as follows; First, the height-range of Geoje-Do is $0{\sim}580m$, and the average elevation of it is 124m. Volcanic and granite region is mainly appeared at high elevation-region. But, we can't find out outstanding difference of elevation, according to its geology. The second. the slope-range of Geoje-Do is $0{\sim}52$ degree, and the average slope of it is 17.6 degree. The slope of volcanic and granite area is more steeper than any other region. But the results of analysis of the geology in Geojo-Do, don't show outstanding difference of the slope. The third, the area-rate of the aspect of Geoje-Do is almost same in all direction. And the area-rate of south-west direction is the highest. According to the geology of Geoje-Do, granite is distributed the most widely, and the area of volcanic and granite occupy 60% of entire island's area. According to analysis of influence of geology with elevation, geology has little relationship with elevation. According to analysis of geology and drainage network, streams are inclined to be developed well in Alluvium area. Drainage network is well developed throughout the entire island, except southeast area. The highest order of stream is 4 in 1:25,000 topographic map. The density of stream in Geoje-Do is very high, such as 1.6. The bifurcation-ratio of stream is also higher than 4 in all order. The length-ratio of stream is ranged from 1.24 to 3.25. According to the relationship between order and elevation. order is the greater, elevation is the lower. According to the relationship between order and slope, order is the greater, slope is the gentler. In this study, we use DTED Data, and compare it with topographic map data. According to the comparison, there is a little difference between DTED data and topographic map data. Therefore, to use DTED data in landform analysis, it is required coordinate matching process. This process is very important, and take very long time. Thus, if you use DTED in landform analysis, some processes are required. DTED data can be taken very easily, but its using is not simple. Because coordinate adjust is very hard work.

• Korean Journal of Environment and Ecology
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• v.14 no.3
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• pp.167-174
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• 2000

거제도 남동 해안지역의 한려해상국립공원 보호구역에서 해상자원의 보존을 위한 기초자료를 확보하고자 거제도 일운면 예구리, 남부면 다대리 및 남부면 저구리 해얀지역에서 1999년 6월부터 2000년 3월까지 어류상 조사를 실시하였다. 조사를 통하여 확인된 어류는 총 16목 47목 69속 85 종 2, 789개체가 채집되었으며, 45종이 출현한 농어목(Perciformes), 10종씩 출현한 가자미목 (Pleuronectiformes) 및 횟대목(Scorpaseniformes)의대부분 저서생활을 하는 어류가 주로 채집되었다. 전체 조사기간 동안 가장 만하은 개체가수가 채집된 어류를 줄비늘치(Coelorhyncus multispinulosus) 458개체(16.4%)로 확인되었고 칠서대(Cynoglossus interruptus) 384개채(13.8%), 노랑촉수(Upeneus bensasi) 285개체(10.2%) 등의 순 이었다. 조사시간 6월에 가장 다양하고 풍부한 어류가 채집되었다.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.21 no.2
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• pp.99-104
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• 1985

In order to provide the basic data required for setting up the proper strategies to minimize the future marine pollution in the vicinity sea area of the Geoje Island, the general water quality parameters and dye diffusion experiment were carried out from January to March, 1983. Although TSS and COD level in the investigated sea area showed still slightly lower than the area of Seaside Industrial Complex Zones, seriously increasing due to the construction of heavy industrial plants. Dissolved oxygen showed more than 8 ppm, and inferred still enough for the reservation of the investigated sea area. The dye patches moved south-eastward with forming an elliptical shape and then turned slowly to the area of Kujora during flood tide, and it moved northwestward and then blocked the entrance of Jangseungpo during ebb tide, The diffusibility in the area may be assessed to be quite better than other coastal areas.