• 한국지하수토양환경학회지:지하수토양환경
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• 제29권3호
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• pp.1-13
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• 2024

This study investigated the hydrogeochemical and microbiological characteristics of freshwater on Ulleung Island, a volcanic island in the Ulleung Basin on the East Coast of Korea. The shallow groundwater (CSW, NRGW) and the surface water (SISW) samples are classified as Na-HCO₃ type, reflecting an alkaline rock type and an oxidizing environment due to the influence of a highly permeable pyroclastic rock layer. In contrast, the deep groundwater sample (DMW) is classified as Ca-HCO₃ type, suggesting the influence of deep-sourced carbon dioxide and reducing conditions. Microbial communities in the water samples are generally dominated by Proteobacteria, with the relative abundance of major genera varying depending on water quality and environmental conditions. Network analysis reveals the ecological characteristics of microbial communities adapted to specific environments. The presence of pathogenic genera in the shallow groundwater suggests potential groundwater contamination, necessitating appropriate management to ensure its use as drinking water or domestic water. The findings of this study provide valuable insights into the ecological characteristics of Ulleung Island's groundwater resources and can inform future groundwater management strategies.

• 한국석유지질학회지
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• 제2권2호
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• pp.59-70
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• 1994

탄성파 탐사 단면도와 시추자료들을 이용하여 울릉분지 남쪽 연변부에 대한 신생대 지질구조 및 지구조 진화과정을 연구하였다. 대한해협 하부 기반암에는 일련의 정단층들이 북동-남서 방향으로 발달해 있다. 정단층들은 울릉분지가 초기 리프팅 및 확장의 신장성 지구조운동 동안 형성된 것으로 해석된다. 쓰시마단층대가 대한해협과 쓰시마해협의 경계를 이루며 쓰시마 섬 서측 연안에서 울릉분지 중심부를 향해 북동남서 방향으로 발달했다. 쓰시마해협의 중기 마이오세 및 고기 퇴적층은 압축성 지구조운동에 의한 북동-남서 방향의 습곡 및 단층구조들이 우세하게 발달해 있다. 후기 마이오세에서 제4기 퇴적층은 거의 지층변형을 받지 않았으나, 쓰시마해협에는 동-서 방향의 단층구조들이 우세하게 발달해 있다. 초기 울룽분지는 올리고세의 리프팅에 의해 형성되었으며, 이어서 초기 마이오세 부터 중기 마이오세 초기까지 확장운동과 침강이 활발하게 진행되었다. 이 때 서남 일본지괴는 한반도로부터 분리되어 남동방향으로 이동하였으며, 울릉분지는 발산성 우수주향이동 신장운동을 받으며 인리형 분지(pull-apart basin)를 형성한다. 쓰시마단층대는 한반도와 서남 일본지괴를 분리시키는 주 구조선으로서, 서남 일본진괴가 남동쪽으로 이동할 때 정단층과 함께 우수주향이동 운동을 한다. 중기 마이오세 중기에서 후기 마이오세 초기 동안 울릉분지 남쪽 연변부는 열개운동이 중단되고 압축성 지구조운동에 의한 지층의 융기작용이 일어난다. 서남 일본지괴의 한반도쪽으로의 수렴운동은 울릉분지의 남쪽 연변부에 대해 압축응력을 미쳤으며, 이는 곧 수렴성 좌수 주향이동에 의한 지층의 압축변형을 야기한다. 쓰시마 단층대는 트러스트단층과 함께 좌수 주향이동 단층운동을 한다. 후기 마이오세 중기에서 현재동안 울릉분지 남쪽 연변부는 압축성 지구조 운동의 지배를 받는다. 쓰시마 단층대는 압축응력을 받아 트러스트단층 운동이 일어난다.

• 대한수의학회지
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• 제58권3호
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• pp.147-151
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• 2018

We assessed the seroprevalence of Coxiella burnetii (C. burnetii) in cattle on Ulleung Island, Korea in a population-based follow up study for 4 years and determined the spatial distribution and risk factors associated with C. burnetii. The seroprevalence of C. burnetii was determined to be 1.4-2.0% during 2011-2014. Overall, nine cattle from three farms that tested seropositive showed C. burnetii antibody seroconversions between 2011 and 2014. The number of seropositive cattle was low, suggesting that movement of and contact between animals was possible risk factors for the transmission of C. burnetii.

• Mycobiology
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• 제42권3호
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• pp.282-285
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• 2014

A fungal isolate EML-NCP01 was recovered from agricultural soil in Ulleung Island, Korea. Phylogenetic analysis of internal transcribed spacer and ${\beta}$-tubulin genes identified the isolate as the Penicillium species P. raphiae. Morphologically, the EML-NCP01 isolate was identical to the previous description of P. raphiae. The species presented here has not been reported in Korea.

• Fisheries and Aquatic Sciences
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• 제3권1호
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• pp.8-13
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• 2000

Monthly mean chlorophyll concentration in the East Sea was estimated from the ocean color observed by the Coastal Zone Color Scanner (CZCS) on Nimbus-7 satellite which had performed various remote sensing missions from 1979 to 1986. The areas of high chlorophyll concentration were found in the sea between Siberia coast and Sakhalin Island, in the Donghan Bay and in the Ulleung Basin. In the southwestern East Sea, especially in the area near Ulleung Island, the yearly maximum chlorophyll concentration occurred in December. The chlorophyll concentration in Ulleung Basin in December was about two times higher than during spring bloom in April. The early winter bloom occurred in the warm side of the front that was formed between warm water from the East China Sea and nutrition rich cold water from the northern East Sea.

• Journal of the korean society of oceanography
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• 제37권1호
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• pp.20-26
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• 2002

The offshore extension of the East Korean Warm Current (EKWC) mostly turns anti-cyclonically around the Ulleung Warm Eddy (UWE). This fact needs to be dynamically explained because a rectilinear stream past a circular cylinder is normally expected to have a flow pattern symmetric about the stream axis. For this purpose, a simple analytical model is presented in this paper. This model shows that the EKWC's tendency to be anti-cyclonic around the UWE is due to the anti cyclonic circulation generated around the UWE. This tendency results from the geostrophic adjustment between the UWE and the ambient EKWC water. As the strength of the UWE decreases, relative to the EKWC, this model shows that the flow pattern gradually changes from circular to rectilinear.

• 한국환경과학회:학술대회논문집
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• 한국환경과학회 2003년도 International Symposium on Clean Environment
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• pp.145-150
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• 2003

16 APEX floats, autonomous profiling floats deployed as part of the Array for Real-time Geostrophic Oceanography (ARGO) program, are used to understand the currents at 800 m underwater in the southwestern East Sea. The flow penetrates into the Ulleung basin (UB) through two paths： an extension of the southward flowing the North Korean Cold Water along the east coast of Korea and between Ulleung Island and Dok island. Flows at 800 m are observed range 0.2 to 4.29 cm/sec and the variability in the north in the DB is stronger than that in the south. The eddy kinetic energy is found a few $cm^{2}$ $S^{-2}$. In the UB, cyclonic flows from 0.3 - 1.6 cm/see are observed with the bottom topography.

• Ocean and Polar Research
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• 제21권2호
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• pp.87-97
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• 1999

To estimate absolute transports by advection in the southwestern East Sea (Japan Sea), an inverse method was applied to CTD data obtained in July 1993. The relative velocities are calculated using the thermal wind equation. The inverse model was formulated to obtain a reference velocity based on the mass conservation in each of four vertical layers within a region enclosed by hydrographic sections and the coastal boundary. The flow patterns in the surface layer are clockwise and anti-clockwise in the regions south and northwest of Ulleung Island, respectively, and a strong northward flow appears in between them. In the second layer, the flow fields are generally weak. The inverse calculation yields the southward flow along the coast, and this suggests that the subsurface low salinity water in the Ulleung Basin is supplied by the southward transport along the east coast of Korea.

• International Union of Geodesy and Geophysics Korean Journal of Geophysical Research
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• 제24권1호
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• pp.1-10
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• 1996

A detailed bathymetric map is used to construct a morphotectonic map of the Ulleung Basin. The definition of "morphotectonics" and the procedure of the morphotectonic mapping are described in detail. The morphotectonic structural elements of various orders and ranks are also determined using echo-sounding and other geophysical data. Preliminary analysis shows that the newly determined morpho-structural elements coincide with the locations of deeper tectonic features established by the geophysical evidences of the inner sedimentary and/or crustal sections. Therefore, the tectonic zone of the Ulleung Basin has imprinted the patterns of the inherited evolution since Neogene.e Neogene.

• 한국환경과학회:학술대회논문집
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• 한국환경과학회 1999년도 임시총회 및 가을 학술발표회 초록집 The Korean Environmental Sciences Society
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• pp.88-91
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• 1999

Temperature data observed by NERDA and the satellite infrared imagery off the east coast of Korea from 1994 to 1998 for 5 years were analyzed to study the distribution, temporal change, and structure of mesoscale eddies appearing almost permanently off the east coast of Korea. Typically, the eddy distribution can be characterized by two cases; two-eddy case and three-eddy case. In 1995 and 1996, there were only two eddies, one northeast of Sokcho and the other around the Ulleung Island. In 1994, 1997 and 1998, three eddies were located off Wonsan, Sokcho and Youngduk. For two-eddy case, the Ulleung Eddy surrounded the Ulleung Island, whereas this eddy is located south of the island in three-eddy case.