• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.9 no.1
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• pp.1-12
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• 2004

Sedimentary facies and high-resolution echo facies were analyzed to elucidate sedimentation pattern of the late Quaternary glacial-marine deposits in the northern continental margin of the South Shetland Islands. Six sedimentary facies are classified, based on grain texture and sedimentary structures in gravity cores. The high-resolution (3.5 ㎑) echo characters are classified into 6 echo facies on the basis of clarity, continuity, and shape of bottom and subbottom echoes together with seafloor topography. Distribution of the echo and sedimentary facies suggest that there was a significant change in sedimentation pattern between the Last Glacial Maximum (LGM) and subsequent glacier-retreating period. When the grounded glaciers extended to the present shelfbreak during LGM, coarse-grained subglacial tills were widespread in the shelf area, and deep troughs in the shelf were carved beneath the fast-flowing ice steam. As the glacial margin retreated landward after LGM, dense meltwater plumes released from the retreating ice-front were funneled along the glacier-carved troughs, and accumulated channel- or cannyon-fill deposits in the shelf and the upper to mid slope. At that time, slope sediments seem to have been reworked by slope failures and unsteady contour currents, and further transported by fine-grained turbidity currents along the South Shetland Trench. After the glacial retreat, sediments in the shelf and slope areas have been mainly introduced by persistent (hemi) pelagic settling, and fine-grained turbidity currents frequently occur along the axis of the South Shetland Trench.

• 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.

• 한국해양학회지
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• v.25 no.2
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• pp.74-83
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• 1990

The similarity in Mesozoic geology between the Antarctic Peninsula and South America indicates the possibility that they had situated along the same tectonics line before the separation of southwestern Gondwanaland. The igneous activity around the Antarctic Peninsula, including the South Shetland islands, can be correlated with the South American Cordillera Orogeny due to the subduction of Farallon/Phoenix plate until late Mesozoic. However igneous activity in Tertiary correlates with the tectonics movement accompanying the formations of Drake passage and Scotian sea. The south Shetland islands form a Jurassic-Quaternary miasmatic island arc on the sialic basement of schist and deformed sedimentary rocks. Forming of the South Shetland Islands arc began during the latest Jurassic or earliest Cretaceous from the southwestern part of the archipelago. The igneous activity migrated northeasterly and continued in most areas until late Tertiary. The entire arc-forming period, between late Jurassic and late tertiary times, was characterized by emplacement and eruption of magmas of intermediate between island-arc tholeiite and calc-alkaline types. However, Quaternary volcanic rocks show strong alkaline affinities which corresponds to the switch from compressional to intra: plate tensional tectonics. The rocks of late Cretaceous to Tertiary, mainly found in King George Island, consist of lava of basalt to andesite and intercalated pyroclastic rocks. Some of the volcanic rocks, which ofter called quartz-pyrite lodes'are severely altered and include much content of calcite,silica and pyrite.The stratographic succession of King George Island can be divided into two formation:Fields formation and Hennequin formation.The Fildes formation crops out at the west side of Admiralty Bay n King George Island,while the Hennequin formation at the east side of the bay.These two formtions are thought to be formed contempiranceously.The Fildes formation consists of altered olivine-basalt and basaltic andestie, whereas the Hennequin formation consists of fine-grained hypersthene-augite-andesite.Both formations interclate pyroclastic rocks.

• Journal of the Korean Geographical Society
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• v.41 no.5 s.116
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• pp.513-526
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• 2006

The timing and extent of glaciations during the Late Quaternary in the South Shetland Islands, West Antarctica were defined using field mapping, geomorphic analysis and radiocarbon dating. Landforms of glacial erosion and deposition, in particular subglacial meltwater channel erosion, suggest that at least three glaciations occurred during the late Quaternary within the study region. During the global LGM, glacial troughs (such as Maxwell Bay and Admiralty Bay) were overdeepened by an ice stream moving south from $an\sim1000m-thick$ ice cap centered on the present-day continental shelf to the north. This ice was responsible for the subglacial meltwater channel erosion, and glacial polished and striated bedrock on the Fildes Peninsula. The recent local glaciations occurred about 2,000 years ago and during Little Ice Age (LIA). During these glaciations, glaciers were less extensive than the previous one and less erosive as a cold-based ice

• 월간 기계설비
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• s.234
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• pp.45-53
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• 2010

지난 1988년 2월 남극반도 남쉐틀랜드 군도의 킹조지섬과 넬슨섬으로 둘러싸인 맥스웰만 연안에 건설된 남극세종과학기지. 우리나라는 지구상의 유일한 비오염 지역인 극지 연구를 위해 세종기지를 건설하고 연구활동을 벌이고 있다. 세종기지 건설은 현대그룹의 현대건설, 현대엔지니어링, 현대중공업이 수행했다. 세종기지는 과학사적 의미와 함께 혹독한 자연환경을 극복하고 건설에 성공했다는 점에서 국내 건설사의 한 페이지를 장식하는 시설물이다. 이제 제2남극대륙기지 건설이 추진 중이다. 현재 건설 후보지 정밀 조사 중으로 정밀조사가 끝나면 건설사 선정 등 사업이 본격적으로 진행될 예정이다. 제2남극대륙기지 건설에 어떤 건설사 및 설비건설업체가 참여할지 주목된다. 한국해양연구원 극지연구소가 제공한 자료와 건설사 취재 등을 토대로 세종과학기지 건설과정을 살펴보고 제2남극대륙기지 건설계획을 전망해본다.

• Ocean and Polar Research
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• v.25 no.4
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• pp.557-567
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• 2003

High-resolution (3.5 kHz) subbottom profiles were analyzed in order to reveal sedimentation pattern of late Quaternary in the northern South Shetland continental margin and the South Scotia Sea, Antarctica. On the basis of clarity, continuity and geometry of surface and subbottom echoes together with seafloor topography, high-resolution echo characters are classified into eight echo types which represent rock basements (echo type III-1), coarse-grained subglacial till or moraine (echo type I-1), slides/slumps (echo type IV), debris-flow deposits (echo types II-3 and III-2), and bottom-current deposits (echo types I-2, II-1 and II-2). Subglacial till or moraine (echo type I-1) is mostly present in the lower continental shelf and upper continental slope of the northern South Shetland continental margin, which changes downslope to slides/slumps (echo type IV) and debris-flow deposits (echo types II-3 and III-2) in the middle to lower continental slope. This distribution suggests that the continental slopes of the northern South Shetland continental margin were mostly affected by downslope gravitational processes. Further downslope, bottom-current sediments (echo type I-2) deposited by the southwestward flowing Antarctic Deep Water (ADW) occur at the South Shetland Trench, reflecting an Interaction between mass flows and bottom currents in the area. In contrast to the northern South Shetland continental margin, the South Scotia Sea is dominated by bottom-current deposits (echo types II-1 and II-2), indicating that the sedimentation was mostly controlled by the westward flowing ADW. Flow intensity of the ADW has increased in the relative topographic highs, forming thin covers of coarse-grained contourites (echo type II-1), whereas it has decreased in the relative topographic lows, depositing thick, fine-grained contourites (echo type II-2). The poor development of wave geometry in the fine-grained bottom-current deposits (echo type II-2) is suggestive of the unsteady nature of the ADW flow.