• 제목/요약/키워드: 남극 반도

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Surface Flux Measurements at King Sejong Station in West Antarctica: I. Turbulent Characteristics and Sensible Beat Flux (남극 세종기지에서의 지표 플럭스 관측: I. 난류 특성과 현열 플럭스)

  • Choi, Tae-Jin;Lee, Bang-Yong;Lee, Hee-Choon;Shim, Jae-Seol
    • Ocean and Polar Research
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    • v.26 no.3
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    • pp.453-463
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    • 2004
  • The Antarctic Peninsula is important in terms of global warming research due to pronounced increase of air temperature over the last century. The first eddy covariance system was established at King Sejong Station located in the northern region of the Antarctic Peninsula in December of 2002 and has been operated over one year. Here, we analyze turbulent characteristics to determine quality control criteria for turbulent sensible heat flux data as well as to diagnose the possibility of long term eddy covariance measurement under extreme weather conditions of the Antarctic Peninsula. We also report the preliminary result on sensible heat flux. Based on the analyses on turbulent characteristics such as integral turbulence characteristics of vertical velocity (w) and heat (T), stationarity test and investigation of correlation coefficient, they fallow the Monin-Obukhov similarity and eddy covariance flux data were reliable. ${\sim}47%$ of total retrieved sensible heat flux data could be used for further analysis. Daytime averaged sensible heat flux showed a pronounced seasonal variation, with a maximum of up to $300Wm^{-2}$ in summer. In conclusion, continuous and long-term eddy covariance measurement may be possible at the study site and the land surface may influence the atmosphere significantly through heat transport in summer.

Hydrothermal Alteration and Mineralization in the Granodioritic Stock of the Barton Peninsula, King George Island, Antarctica (남극 킹죠지섬 바톤반도 화강섬록암의 열수변질과 광화작용)

  • Hwang, Jeong;Lee, Jong Ik
    • Economic and Environmental Geology
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    • v.31 no.3
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    • pp.171-183
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    • 1998
  • Early Tertiary volcanics, volcanoclastics and granodiorite occur in the Barton Peninsula, King George Island, Antarctica. In the granodioritic stock and volcanic rocks, propylitic alteration characterized by actinolite, epidote, chlorite and calcite is widespread, and disseminations and veinlets of sulfide minerals such as pyrite, chalcopyrite and bornite are ubiquitious. The study on the hydrothermal alteration near granodioritic stock can be summarized as follows; (1) granodiorite intrusion is a small, high level stock associated with calc-alkaline volcanism, and have high copper content, (2) high temperature type of propylitic alteration and common occurrence of copper sulfides in and around granodiorite intrusion, (3) low ${\delta}^{34}S$ values of pyrites by oxidational conditions of sulfide deposition, (4) low ${\delta}^{34}S$ values of quartz and feldspar in the granodiorite, and isotopic non-equilibrium by hydrothermal alteration. It suggest that hyrothermal alteration and mineralization near granodioritc stock should be genetically related to granodiorite intrusion in the Barton Peninsula.

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Diatom Assemblages and its Paleoceanography of the Holocene Glaciomarine Sediments from the Western Antarctic Peninsula shelf, Antarctica (남극반도 서 대륙붕의 빙해양 퇴적물의 규조군집 특성과 고해양 변화)

  • Shin, Yu-Na;Kim, Yea-Dong;Kang, Cheon-Yoon;Yoon, Ho-Il
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.6 no.3
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    • pp.152-163
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    • 2001
  • Based upon the sedimentological, geochemical and micropaleontological analyses of two sediment cores from the Antarctic Peninsula (AP), three distinct lithological units can be recognized: (1) ice-proximal an/or ice-distal diamictons in the lower part of the cores, accumulated just seaward of the grounding line of the ice shlef until 11,000 yrs BP; (2) diatomaceous mud between 6,000 and 2,500 yrs BP in the middle part, resulted from a large influx of organic materials by enhanced production of open marine condition; (3) diatomaceous sandy mud since 2,500 yrs BP, characterized by an increase in sand content and decrease in TOC and diatom abundance in the lower layers, which reflects the formation of more extensive and seasonally persistent sea ice. Based on the C-14 radiocarbon dating, the sub-ice shlef deposition of the diamicton on the AP western shelf completed around 11,000 yrs BP. Colder condition was reinstated between 12,800 and 11,600 BP with a dropin TOC content and diatom abundance, which is coincident with the Younger Dryas event in the North Atlanticregion. At this time, the ice shelf, that is now absent in the study area, appears to advance as evidenced by an abrupt increase in sea-ice taxa. A climatic optimum is recognized between 9,000 and 2,500 BP, coincide witha mid-Holocene climatic optimum 'Hypsithermal Warm Period' from the other Antarctic sites. During this time, diatomaceous mud accumulated by a large influx of organic materials by enhanced production occurred in openmarine condition. Around 2,500 BP, diatomaceous sandy mud reflects the formation of more extensive and seasonally persistent sea ice, coincident with the onset of the Neoglacial in the Antarctic. Our results provide evidence of climatic change from the Antarctic Peninsula`s western shelf that helps in determining the existence and timing of Holocene milennial-scale climatic events in the Southern Hemisphere.

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Physico-chemical Characteristics of Soil in the Vicinity of King Sejong Station, King George Island, Antarctica (남극 킹조지섬 세종기지 주변지역 토양의 물리화학적 특성)

  • Choi, Ik-Won;Park, Yang-Ju;Seo, Dong-Cheol;Kang, Se-Won;Jeon, Weon-Tai;Kang, Ui-Gum;Sung, Hwan-Hoo;Hur, Tai-Young;Heo, Jong-Soo;Cho, Ju-Sik
    • Korean Journal of Soil Science and Fertilizer
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    • v.44 no.5
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    • pp.709-716
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    • 2011
  • In order to collect basic data of soil environment in the Vicinity of King Sejong Station, King George Island, Antarctica, the physico-chemical characteristics of soils were investigated. Soil samples were collected in Barton Peninsula from 13 sites according to direction from the Sejong Cape. Soils from 13 sites were divided into three groups. The sand percentage of soils were much higher as above 90% than silt and clay percentages of soils at the all sites. Soil texture was classified sandy (10 sites) and loamy sand (3 sites). In distribution characteristics at different soil particles according to direction, large particles ($>500{\mu}m$) were higher in the order of Group 1 (Marian cove coast regions) > Group 2 (Inland regions) > Group 3 (Maxwell bay coast regions). On the other hand, small particles ($<355{\mu}m$) were higher in the order of Group 3 > Group 2 > Group 1. Chemical characteristic of soils showed significant differences at different areas. pH ranged 4.5-6.7, showing it was slightly acid and EC ranged $0.06-0.16dS\;m^{-1}$. T-N, OM and T-C contents were high at #6, #8, #12 and #13 sites. T-P and P2O5 contents were high at #9 and #12 sites. The results of this study will be helpful to understand soil environment in the Antarctic Peninsula and surrounding islands.

Chemical Weathering of Glacial Debris of the Barton Peninsula of King George Island, South Shetland Islands, Antarctica: Microtextural Evidences (남극 사우스셰틀란드 킹죠지섬 바톤반도 빙하쇄설물의 화학적 풍화작용: 미조직학적 증거)

    • Journal of the Mineralogical Society of Korea
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    • v.16 no.2
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    • pp.181-189
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    • 2003
  • Diverse microtextures and secondary minerals formed by chemical weathering were observed in the glacial debris of King George Island. Weathering rind was observed in the block of basaltic andesite tuff due to dissolution of calcite producing voids. Eolian volcanic glass altered to mixtrure of allophane-like materials and iron oxyhydroxides at grain edges with relative concentration of Al. Fe, and Ti. Biotite in granodiorite area was transfarmed to vermiculite and interstratified biotite-vermiculite or very rarely to kaolinite and gibbsite. Pyrite in the hydrothermal alteration zone was repalced by iron oxides, resulting in sulfuric acid which locally accelerated alteration of chlorite to expandable clay minerals. Weathering of plagiociase and K-feldspar was negligible. Although glacial debris of the Barton Peninsula has undergone weak chemical weathering with formation of some secondary minerals, massive formation of smectite, abundant in nearby marine sediments, didn't occur.

OBSERVATIONS OF UPPER THERMOSPHERIC TEMPERATURES USING A GROUND-BASED OPTICAL INSTRUMENT AT THE KING SEJONGSTATION, ANTARCTIC (남극 세종기지 광학 간섭계를 이용한 열권 상부 온도 관측)

  • Chung, Jong-Kyun;Won, Young-In;Lee, Bang-Yong;Kim, Jhoon
    • Journal of Astronomy and Space Sciences
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    • v.15 no.1
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    • pp.139-150
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    • 1998
  • We measured the terrestrial nightglow of OI $6300{\AA}$ in the thermosphere (~250km) using a ground-based Fabry-Perot interferometer at the King Sejong Station, Antarcticfrom March through September, 1997. The King Sejong Station is located at high latitude geographically ($62.22^{\circ}S,\;301.25^{\circ}E$) but at mid latitude geomagnetically ($50.62^{\circ}S,\;7.51^{\circ}E$). It is therefore the strategic location to measure the temperatures of the thermosphere in the Southern Hemisphere associated with both solar and geomagnetic activities. In this study, we analyzed the observed temperatures inrelation to F10.7 and Kp indices to examine the effect of the solar and the geomagneticactivities on high-latitude neutral thermosphere. During the observing period, the solaractivity was at its minimum. The measured temperatures are usually in the range between about 600~1000 K with some seasonal variation and are higher than those predicted by semi-empirical model, VSH (Vector Spherical Harmonics) and empirical model, MSIS (Mass-Spectrometer-Incoherent-Scatter)-86.

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Chartacteristics of Water-bottom Reflection Coefficients in Bransfield Strait, Antarctic Peninsula (남극 브랜스필드 해협의 해저면 반사계수 특성)

  • Jin, Yeong Geun;Hong, Jong Guk;Lee, Deok Gi
    • Journal of the Korean Geophysical Society
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    • v.2 no.4
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    • pp.241-250
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    • 1999
  • Reflection coefficients of the seafloor have been calculated from the amplitude ratio of secondary to primary water bottom reflection in seismic data obtained from Bransfield Strait, Antarctic Peninsula. Test processing for the coefficients shows that moving average is effective to reduce severe fluctuation of the coefficient measured at each point. Relationship between the coefficients and the properties of water bottom is analyzed to illuminate geological environment. In the central Bransfield Basin, the magnitude of reflection coefficients decreases as it is distant from the sedimentary sources. Reflection coefficients range from 0.12 to 0.2 near the continental slope of the basin, and from 0.1 to 0.12 in the basin floor. In the western Bransfield basin, reflection coefficients between 0.2 to 0.3 are obtained from the area eroded by glacial movement. On the volcanic structures near Deception Island, the coefficients show relatively high values more than 0.2. Paleo-geological structures uplifted by tectonic movement and outcropped by glacial erosion have relatively high coefficients.

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Genome sequence of Caballeronia sordidicola strain PAMC 26510 isolated from Psoroma sp., an Antarctic lichen (남극 지의류에서 분리한 Caballeronia sordidicola균주 PAMC 26510의 유전체 서열 분석)

  • Yang, Jhung Ahn;Hong, Soon Gyu;Oh, Hyun-Myung
    • Korean Journal of Microbiology
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    • v.53 no.2
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    • pp.137-140
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    • 2017
  • Caballeronia sordidicola strain PAMC 26510 was isolated from Psoroma sp., a lichen material, collected from Barton Peninsula of King George Island in Antarctica. The draft genome sequence of PAMC 26510 consisted of 224 contigs and they was 7,872,143 base pairs with 59.7% G+C content. The genome included 7,580 protein coding sequences and 6 ribosomal RNA genes and 46 tRNA genes. The strain PAMC 26510 is also a metabolic generalist as we have observed in previous genomic studies in the arctic strain of Caballeronia sordidicola. The draft genomic sequences of PAMC 26510 had six CRISPR arrays on six contigs, and there were two clusters of CRISPR-associated genes that were linked with respective CRISPR arrays.

K-Ar Age of the flutonic Rock fragments Discovered from the Deception Island and Its Geologic Implication (디셉션 섬에서 발견된 심성암편의 K-Ar 연령과 지질학적 의미)

  • Park, Joo-Un;Park, Kye-Hun;Lee, Jong-Ik;Park, Byong-Kwon
    • The Journal of the Petrological Society of Korea
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    • v.17 no.1
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    • pp.36-43
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    • 2008
  • Many plutonic rock fragments of granitic composition were collected from the Deception Island. We obtained K-Ar ages of $62.5{\pm}1.2\;Ma$ and $140.7{\pm}2.7\;Ma$ from the two samples. Such result contradicts the general belief that most of the volcanic rocks of Deception Island are products of very recent activities and their maximum age does not exceed 200 ka. On the other hand, Mesozoic to Cenozoic rocks produced by subduction-related active magmatism have been reported from both South Shetland Islands and Antarctic Peninsula, located to the north and south of the Deception Island respectively. Also, various kinds of plutonic rocks with granitic composition are distributed widely. Therefore, plutonic rock fragments with granitic composition discovered from the Deception Island seem to indicate their derivation by capturing granitic crustal material underlying volcanic edifice during the volcanic activities, instead of differentiation from magmas related with recent volcanism. Ages and rock types of the plutonic rock fragments suggest arc-related origin just as adjacent South Shetland Islands and Antarctic Peninasula.

Mineralogical and Geochemical Characteristics of Soils of Barton Peninsula, King George Island, South Shetland Islands, West Antarctica (서남극 사우스셰틀랜드 킹조지섬 바톤반도 육상 토양의 광물학적, 지화학적 특성)

  • Jung, Jaewoo;Koo, Taehee;Yang, Kiho;Kim, Jinwook
    • Journal of the Mineralogical Society of Korea
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    • v.30 no.1
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    • pp.21-29
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    • 2017
  • Surface soils on Barton Peninsula, King George Island, West Antarctica were investigated to acquire the mineralogical and geochemical data of soil in Antarctica. Multiline of techniques for example, X-ray diffraction (XRD), transmission electron microscopy (TEM)-electron energy loss spectroscopy (EELS), and wet chemistry analysis were performed to measure the composition of clay minerals, Fe-oxidation states, cation exchange capacity, and total cation concentration. Various minerals in sediments such as smectite, illite, chlorite, kaolinite, quartz and plagioclase were identified by XRD. Fe-oxidation states of bulk soils showed 20-40% of Fe(II) which would be ascribed to the reduction of Fe in clays as well as Fe-bearing minerals. Moreover, redox states of Fe in smectite structure was a ~57% of Fe(III) consistent to the values for the bulk soils. The cation exchange capacity of bulk soils ranged from 100 to 300 meq/kg and differences were not significantly measured for the sampling locations. Total cations (Mg, K, Na, Al, Fe) of bulk soils varies, contrast to the heavy metals (Co, Ni, Cu, Zn, Mn). These results suggested that composition of bed rocks influenced the distribution of elements in soil environments and soils containing clay compositions may went through the bio/geochemical alteration.