• Journal of The Geomorphological Association of Korea
• /
• v.15 no.2
• /
• pp.11-24
• /
• 2008

Stratified slope was formed on the SSE-facing slope in the southwest region of Haenam, South Korea. Field and laboratory investigations into the geomorphology and sedimentology of stratified slope deposit that is inactive. Outcrops of this deposit show an alteration of coarse debris-supported matrix and tiny debris-supported matrix layers. Sedimentological analysis(particle-size analysis) indicates that this deposit is not fluvial process or only gravitation like rock-fall. Many clasts and fine materials on the slope is supposed to be product by congelifraction under Pleistocene periglacial climatic environment. Also The processes responsible for the genesis of this deposit probably are to move downward by gelifluction and to remove fine materials by slope wash in thawing cycle and in situ debris congelifraction on gelifluction slope. Now It is impossible to account for the time range of genesis(diurnal, seasonal). In conclusion, this stratified slope formed in cold and humid periglacial environmental in pleistocene, therefore, this slope is a periglacial relic landform, indicates that in south korea there was a cold and humid paleo-climate such as periglacial environmen.

• Journal of The Geomorphological Association of Korea
• /
• v.19 no.1
• /
• pp.83-97
• /
• 2012

Slopes of Seoseokdea~ Jangbuljae, at Mt. Moodeung, appears repeatedly the cliffs are mostly greater than $70^{\circ}$, and the planations maintain around $5^{\circ}$ in general. They studied the creation of development environments, cryoplanation are mainly facing the southwest. It is assumed that rock falling had been wostly occurred under a periglacial environment through jointing due to repeated freezing and thawing. Planation at the bottom of Columnar joint are described structural benches. Movement precesses of planation matrix are solifluction or jelifluction. The result of age determination of the slopes in Jangbuljae tells that the upper part of Ibseokdae has been remaining exposed to the land surface from 110,000 year ago. The blocks in the bottom part has been exposed to the surface around 10,000 year ago while Jangbuljae has been exposed to the surface about 50,000 year ago. It was assumed that they moved to the current location since being separated from columnar joint after exposure to the surface.

• Journal of the Korean Geographical Society
• /
• v.33 no.2
• /
• pp.191-208
• /
• 1998

제주도의 기온온난화가 한라산 고산식물 분포에 미치는 영향에 대한 연구의 하나로 한라산 고산식물 8종의 수평 및 수직 분포역과 생육환경이 조사되었다. 그 결과 희귀하거나 멸종 위기 상태에 있는 고산식물들에 관한 생물지리학적 기초 자료와 정보가 축적되었다. 한라산 고산식물은 분포특성에 따라 8가지 유형으로 분류되며, 그 중 70퍼센트 정도가 한반도의 고산지나 일본열도의 것들과 공통적인 것으로 밝혀졌다. 이들은 빙하기 동안 동북아시아에서 한반도를 거쳐 제주도로 유입되었고, 일부는 일본열도에 전파된 것으로 생각된다. 현재 이들 고산식물은 열악한 기후, 척박한 토질과 지질 그리고 동결과 융해가 반복되는 주빙하성 환경에 적응하여 산정부 일대에 주로 분포한다. 본 연구는 한라산 고산식물의 분포와 과거 및 현재 환경과의 관계에 대한 기초 자료를 구축하여, 한반도의 자연환경 변천사를 파악하고, 기온온난화가 지속될 때 한라산 고산경관과 생태계가 당면할 문제를 파악하고 대안을 제시하는데 필요한 정보를 제공할 것으로 기대된다.

• The Korean Journal of Malacology
• /
• v.10 no.2
• /
• pp.10-23
• /
• 1994

패류화석은 지구를 이루는 퇴적암 중 석회암을 이루고 있는 주요 구성원 중의 하나이다. 지난 20년간 지질학자 및 해양학자들은 주로 심해에 쌓여 있는 퇴적물 중의 미화석(microfossil)을 이용하여 과거의 기후 및 해양의조건을 규명하기 위하여 많은 노력을 하여왔다. 그 결과로서 지질학적 시대 중 중생대 이후로부터 신생대에 이르기까지 지구 전반에 영향을 주었던 고기후에 대한 많은 정보가 얻어졌다. 또한 일부 학자들에 의하여 천해에 서식하였던 여러 화석들의 생태와 지화학적 분석(geochemical analysis)을 통하여 지엽적인 고기후(paleoclimate) 및 고해양학적(paleoceanographic)이해도 증진되어 온 것이 사실이다. 천해에 서식하고 있는 석회질 골격(calcareous skeleton)을 만드는 생물종들은 주로 생화확적인 작용을 통하여 아라고나이트와 방해석이라는 탄산염 광물을 침전시킨다. 특히 이 중에서 아라고나이트라는 광물은 불안정하여 속성작용 (퇴적물이 쌓인 후 거치는 물리, 화학적 작용)동안에 방해석으로 변하게 된다. 따라서 특이한 속성환경의 조건에 의해 아라고나이트로 보존되어 있는 패류를 제외하고는 주로 방해석으로 이루어진 화석의 분석을 통하여 고환경 복원을 위한 여러 정보를 얻을 수 있다. 이를 근거로 하여 분석 대상이 주로 된 것은 완족류나 방해석으로 이루어진 이매패류(e.g., 굴등)이었다.우리나라에서는 최근에 이르러서야 패류 화석의 지화학적 분석을 통하여 고해양학적 연구가 수행되기 시작하였다. 신생대 제 3기 마이오세에 해당하는 포항 부근에서 발견되는 연체동물 화석들은 변질이 안된 상태로서 우리에게 매우 귀중한 고해양학적 정보를 제공한다. 과거에 생물이 자랐던 성장 온도는 산소 동위원소의 비를 측정하여 구할 수 있는데 그결과에 의하면 해수의 온도가 현재보다 약간 높았음을 지시한다. 제주도 내의 서귀포 부근에서는 현재 천연기념물로 지정되어 있는 서귀포층내에서 많은 화석들이 산출되고 있다. 이 시대는 빙하기와 간빙기가 교호하던 시대로서, 분석 결과에 의하면 서귀포층이 쌓일 당시에 우리 나라는 빙하기의 영향을 받았던 것으로 생각된다.

• Journal of the Korean association of regional geographers
• /
• v.2 no.2
• /
• pp.173-182
• /
• 1996

The intent of this paper is to examine the talus in Chon-hwang-san in the southern part of Korean Peninsula, and then analyze its geomorphic feature and origin. The research is summarized as follows; (1) The talus is 220m long and the range of the width from 10 to 75m. The mean gradient is $33^{\circ}$ and the mean block size is $110{\times}59cm$(long axis$\times$short axis). The overall appearance of the talus is tongue-shaped and the geology of the constituent blocks is dacite. (2) This talus has two particular geomorphic landscapes. One is that the talus has not free face as source of blocks back of itself; the free face of the talus has been parallel retreated to disappearance by frost attack. The other is that the upper part of the talus is on the ridge. (3) This talus is classified into rock fall talus type, and the shape of rock fragments is angular. When considered in conjunction with face of being mentioned above, the morphology and lithology of the talus are best explained on the basis of origin under periglacial environment during late pleistocene time. (4) Most constituent rock debris are now lichen-covered, or covered with a mantle of weathering. There is no evidence of appreciable movement and for supplying block. Therefore, the talus appears to be relict or fossil form stage, currently.

• Journal of the Korean association of regional geographers
• /
• v.3 no.1
• /
• pp.165-182
• /
• 1997

The aim of this paper is to clarify geomorphic features on talus within ${\check{O}}rumkol$ and the origin of ${\check{O}}rumkol$. ${\check{O}}rumkol$ is located in Milyang of Kyungnam province, in South Korea. ${\check{O}}rumkol$ is good area to study talus. because it is characterized by following three geomorphic landscapes : free face surrounding ${\check{O}}rumkol$ ; ${\check{O}}rumkol$ with deep and wide valley floor ; lots of taluses typically developing within ${\check{O}}rumkol$. The main results can be summarized as follows: 1) The origin of ${\check{O}}rumkol$ may be suggested two assumptions : one is that its origin have been resulted from intrusion structure(intrusive rock might capture less resistant rock as tuff) ; the other is that its origin have been resulted from volcanic depression after intrusion or eruption. But these assumptions are not obvious. therefore more geological evidences will be supplemented after this 2) The characteristics of ${\check{O}}rumkol$ talus (1) Pattern ${\check{O}}rumkol$ taluses are tongue-shaped or cone-shaped in appearance. They are $50{\sim}200m$ in length and the range of the maximum width from 25 to 115m and one of their mean slope gradient from 32 to $36^{\circ}$ (2) Origin ${\check{O}}rumkol$ taluses have been formed under periglacial environment in the last glacial age and they are classified into rock fall talus type, considering in conjunction with the shape, hardness, sorting, weathering conditions of constituent debris. (3) The stage of landform development ${\check{O}}rumkol$ talus slope profiles are mainly concave slope. This concave slope type was eventually caused by talus creep at the lower end of the talus. That means new additions of debris from the free face have virtually ceased and there is no evidence of recent motion in the deposit. Now it is predominant that vegetation cover is gradually increasingly. Therefore ${\check{O}}rumkol$ taluses appear to be relict form stage. at present.

• Journal of the Korean association of regional geographers
• /
• v.5 no.2
• /
• pp.133-142
• /
• 1999

The wetland is very important ecologically as a habitat of diverse organisms. The purpose of this paper is to elucidate the morphogenetic environment of Jilmoe Bog found in the Odae Mountain National Park Jilmoe Bog is located in the high etchplain(1,060m) where Daebo Granite which had intruded in Jura epoch of Mesozoic era has weathered deeply and has uplifted in the Tertiary. The annual mean temperature of study area is $5.3^{\circ}C$, the annual precipitation is 2,888mm. The minimun temperature of the coldest month(january) is below $-30^{\circ}C$ and the depth of frozen soil is over 1.6m. Jilmoe bog consists of a large bog and a small bog. The length of the large bog is 63m and its width is 42m. The basal surface of Jilmoe bog is uneven. Jilmoe bog is a string bog fanned due to frost actions. In String bog, its surface is wavy with stepped dry hills and net-like troughs crossing hill slope. It seems that string bog is related to the permofrost or seasonal permofrost of cold conifer forest(taiga) zone(where the depth of frozen soil is very deep in the least in winters). String bog is a kind of thermokarst that frozen soil thaws differentially locally in declining permofrost and ground surface becomes irregular. There is turf-banked terracette of width $30{\sim}40cm$ in the headwall of small cirque-type nivation hollow formed at footslope of Maebong mountain around Jilmoe bog. This turf-banked terracette is formed by the frost growth of soil water below grass mat in periglacial climate environment. Where water is plentiful such as a nivation follow${\sim}$valley corridor and a headwall of valley, turf patterned grounds of width $30{\sim}50cm$ are found. This turf patterned ground is 'unclassified patterned ground', earth hummock. In conclusion, Jilmoe bog is a string bog of thermokarst that the relief of ground surface is irregular according to locally differentially thawing of permofrost(frozen soil). Jilmoe bog is high moor, its surroundings belongs to periglacial environment that turf-banked terracette and turf patterned ground are fanned actively.

• Proceedings of the Korean Quaternary Association Conference
• /
• 2004.06a
• /
• pp.46-46
• /
• 2004

Van Mijenfjorden은 스발바드 군도의 Spitsbergen 서부에 위치하는 두 번째로 큰 피오르드로 온난하고 염분도가 높은 북대서양의 표층수가 북극해로 유입되는 Gateway에 위치하기 때문에 전지구적이며 지역적인 기후변화의 영향을 받는 지역이다. 1999년 IMAGES 프로그램의 일환으로 프랑스 탐사선인 'R/V Marion Dufresne'을 이용하여 북극해의 스발바드 군도에 위치하는 Van Mijenfjorden (77$^{\circ}$ 46.87'N and 15$^{\circ}$ 17.81'E)에서 약 18m의 빙ㆍ해양 퇴적물 코아(MD99-2305)를 시추하여 마지막 최대 빙하기 이후의 고환경변화를 연구하였다. AMS 14C 연대 측정에 의하면 diamicton 층인 하부 2m를 제외한 16m의 퇴적층은 지난 12cal. ka BP경에 피오르드에 존재하던 조수빙하(tidewater glacier)가 해빙되기 시작한 이후에 퇴적되었다. 특히 유기지화학 자료와 부유성과 저서성 유공충의 산출양상 그리고 저서성 유공충인 C. reniforme의 산소ㆍ탄소 안정동위원소 비에 의하면 코아 MD99-2305에는 Van Mijenfjorden에서 홀로세 동안에 일어난 퇴적환경변화를 잘 기록하고 있다. 특히 홀로세 동안에 피오르드내의 퇴적환경 변화는 조수빙하의 확장과 후퇴와 밀접한 관계가 있으며, 유기물의 탄소동위원소(13Corg) 비는 -24에서 -22$\textperthousand$ 값의 변화를 보인다. 이는 Van Mijenfjorden 퇴적물에 공급된 유기물은 육상과 해양기원이 혼합되어 퇴적되었음을 지시한다. 지난 12 cal. ka BP 이후 13Corg 값이 뚜렷하게 변하는 것은 Van Mijenfiorden에서 조수빙하의 변동과 표층수에서의 생산력의 변화를 강하게 반영한다. 강하게 반영한다.53%가 이공계 출신, 100대 기업 CEO의 38.4%가 이공계 출신, 대입수능시험에서 자연계 지원비율이 감소 -40.1%('99)\$\longrightarrow$34.7%('00)\$\longrightarrow$29.4%('01)\$\longrightarrow$26.9%('02)\$\longrightarrow$30.3%('03)\$\longrightarrow$31.5%\$\longrightarrow$'04)필요성, 효과적인 운전자 교육 정책 등이 그것이다. 자동차 긴급 피난 차선은 유용한 시설로 여러곳에서 그 기능이 발휘되고 있으므로 많은 고속도로 관계자들은 설계, 시공 및 유지 관리 측면에서 유의해야 할 것이다.미세조직을 광학현미경으로 압출방향에 평행한 방향과 수직방향으로 관찰하였고, 열간 압출재 이방성을 검토하기 위하여 X선 회절분석을 실실하여 결정방위를 확인하였다. 전기 비저항 및 Seebeck 계수 측정을 위하여 각각 2$\times$2$\times$10$mm^3$ 그리고 5$\times$5$\times$10TEX>$mm^3$ 크기의 시편을 준비하였다.준비하였다.전류를 구성하는 주요 입자의 에너지 영역(75~l13keV)에서 가장 높은(0.80) 상관계수를 기록했다. 넷째, 회복기 중에 일어나는 입자들의 유입은 자기폭풍의 지속시간을 연장시키는 경향을 보이며 큰 자기폭풍일수록 현저했다. 주상에서 관측된 이러한 특성은 서브스톰 확장기 활동이 자기폭풍의 발달과 밀접한 관계가 있음을 시사한다.se that were all low in two aspects, named "the Nonsignificant group". And the issues were

• Journal of the Korean association of regional geographers
• /
• v.6 no.2
• /
• pp.71-82
• /
• 2000

The purpose of this paper is to clarify geomorphic features and development on the boulder stream of granitoid in Korea. Considering the purpose and the method of this paper, three boulder streams are selected : Biseulsan(Mt. Biseul) boulder stream (Daegu city), Maneosan (Mt. Maneo) boulder stream(Gyeongnam province), Geumjeongsan(Mt. Geumjeong) boulder stream (Busan city). The boulder streams mentioned above are bigger in scale and more typical in shape than any other ones in the Korean Peninsula. The main results are summarized as follows. 1. The following are the main features of the boulder streams morphology : the mean gradient is $3{\sim}25^{\circ}$, the longer axes of the component boulders within the deposits averaged about 2m in length, the shapes of the component boulders may be both subangular and subrounded features. 2. The formation of the component boulders is associated with deep weathering of granitoid under warm humid conditions, and the downward movement of boulders occurred by solifluction and frost creep under periglacial conditions. 3. The geomorphic development stage of the boulder streams may be classified into four stages. These boulder streams come under fossil landform stage, the 4th stage ; evidence provided by lichens and weathering features indicate inactive or fossil landform. 4. In generally, boulder streams are well developed on shallow valley floors.

• Maritime Security
• /
• v.2 no.1
• /
• pp.151-184
• /
• 2021

Global warming due to climate change is one of the biggest challenges in the 21st century. Global warming is not only a disaster that threatens the global ecosystem but also an opportunity to reduce logistics costs and develop mineral resources by commercializing Arctic routes. The Arctic paradox, in which ecological and environmental threats and new economic opportunities coexist, is expected to have a profound impact on the global environment. As the glaciers disappear, routes through the Arctic Ocean without passing through the Suez and Panama Canals emerged as the 'third route.' This can reduce the distance of existing routes by 30%. Global warming has also brought about changes in the geopolitical paradigm. As Arctic ice begins to melt, the Arctic is no longer a 'constant' but is emerging as the largest geopolitical 'variable' in the 21st century. Accordingly, the Arctic, which was recognized as a 'space of peace and cooperation' in the post-Cold War era, is now facing a new strategic environment in which military and security aspects are emphasized. After the Cold War, the Arctic used to be a place for cooperation centered on environmental protection, but it is once again changing into a stage of competition and confrontation between superpowers, heralding 'Cold War 2.0.' The purpose of this study is to evaluate the strategic value of the Arctic Ocean from geopolitical and geoeconomic perspectives and derive strategic implications by analyzing the dynamics of the New Cold War taking place in the Arctic region.