• 지구물리
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• 제9권3호
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• pp.219-230
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• 2006

Since the key issue that 'the Yangsan fault is seismically an active fault" was raised in 1983, thegeological and geomorphological studies of active fault have been made by many researchers. These studies are mainly focused on the Yangsan fault system(YFS) and Ulsan fault system(UFS) due to many historical earthquakes occurred in this area. There are two different types of active faultings under the ENE-WSW horizontal stress field in the southeastern part of the Korean Peninsula. The NNE-trending YFS is the most prominent right-lateral strike-slip fault and has a continuous trace about 200 km long. Some part of this system has been active during the late Quaternary with evidences clearly recognized on both the northern (Yugyeri and Tosung-ri areas) and southern parts (Eonyang to Tongdosa area) of the YFS. in the southern part, the estimated vertical slip rate is about 0.02 - 0.07 mm/yr, and the lateral slip rate may be several times larger than the vertical rate. The most recent event occurred prior to deposition of Holocene alluvium, in the northern part, the fault trend locally changes to almost N-S, dips to the east and has reverse movement. The average vertical slip rate is estimated to be less than 0.1 mm/yr. The most recent event probably occurred after 1314 years BP (AD 536). The NNW-SSE (or N-S) trending UFS is a predominantly reverse fault that built up U-ie eastern mountain and has been active during U-ie late Quaternary. The fault trace is not straight but irregularly undulates along the foot of the mountain on the east. From the disturbed terraces along U-ie fault, the average vertical slip rate on U-iis system is estimated to be about 0.08.13mm/yr. The latest event is not well studied, but seems to have occurred after the last glacial maximum in the Malbang fault and 14,000 years BP in the Kalgok fault of the UFS. However, important issues such as fault segmentation, recurrence interval, age of Quaternary deposits need further studies.

• 한국해양학회지
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• 제30권6호
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• pp.550-564
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• 1995

공간적으로 평활화하고 저주파 필터를 적용한 1978년부터 1987년까지 10년간의 일별 해상풍 자료를 이용하여 한국 주변해역에서의 해상풍의 시 ${\cdot}$ 공간적 분포특성을 연구하였다. 종관적 분포형태를 위해 해상풍의 연평균과 월평균 분포특성을 검토하였고, 시간적 변동성과 공간적 상관성을 위해 스펙트럼 분석을 하였다. 연평균 wind stress와 curl의 공간형태는 겨울철 월평균 형태와 매우 닮았다. 일년 및 반년주기성이 뚜렷하다. 연구해역에서 종관적 바람은 일년 및 반년 주기에서 공간적 상관성이 매우 높으나 각 해역별로 특징적 공간분포를 보인다. 예를들면, 겨울철 바람은 동해북부, 황해와 동중국해 북부에서는 북풍이 우세한 반면, 동해남부에서는 북서풍이, 동중국해 남부에서는 북동풍이 우세하다. 또한 curl의 경우는 동해북부와 동중국왜 남부에서는 양의 값을 보이나 동해남부와 황해 그리고 동중국해 북부에서는 음의 값을 보인다. 한편, 세력이 대단히 약해지는 여름철 바람은 겨울철 바람과 아주 다르고 열대성 저기압의 빈번한 통과로 동중국해 해상에서 시간변동이 커진다. 시베리아 고기압이 큰 영향을 끼치는 연변동은 북동에서 남서로, 즉 동해북부에서 동해남부 및 황해와 동중국해로 전파되는 경향을 보이나, 반년변동은 반대방향인 남서에서 북동으로 전파되는 점은 주목할 만하다. 반년 주기성은 한반도를 서에서 동으로 횡단하는 온대성 저기압이 봄과 가을에 발달하는 것을 나타내는 것으로 판단된다. 단주기 영역에서는 뚜렷한 주기성이 나타나지 않지만, 0.1 cycles per day (cpd) 이상에서는 황해와 동해의 지역풍이 공간적 상관성이 높고 위상도 주파수에 선형적으로 증가한다. 이러한 선형적 증가는 0.1, 0.3 cpd에서 550, 730 km/d의 위상속도에 해당하며 위상속도는 한반도를 서${\cdot}$동로 통과하는 온대성 저기압의 이동속도와 외형적으로 일치한다.

• 자원환경지질
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• 제12권4호
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• pp.207-221
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• 1979

The studied area occupies the southern part of Haenam peninsula located in the southwestern corner of Korea. The stratigraphic sequences of the area are grouped into following three units in ascending order. (1) Late Cretaceous sedimentary rocks of Uhangri Formation which consist of the alternative beds of black shales and tuffaceous sediments, Hwangsan acidic fine grained tuffs and Jindo rhyolite flows. (2) Late Cretaceous biotite granite and acidic porphyries which intruded the Late Cretaceous sedimentary rocks. (3) Tertiary(?) pitchstone. The study purposes to delineate any of geochemical aspects on the deposition of the sequences, the average amounts of organic materials and the effect to the maturation of hydrocarbonization which has been occured by the intrusives. Sixty nine black shale samples were collected from Uhangri Formation in the northern and southern coasts of the peninsula. Organic carbons, total extracted organic matters and hydrocarbons were mainly determined by the Soxhlet extraction method, together with C-H-N elemental analyses. Based on the field and laboratory studies, the following interpretations have been obtained. (1) The paleohydrostatic condition of the sedimentation which took place was relatively calm and stable to delineate a lacustrine environment. (2) The amounts of organic material were more or less constant throughout the period of the deposition of the sediments. (3) The degree of hydrocarbonization of the Uhangri Formation in the northern coast was taken place higher than that in the southern coast due to the differences of thermal effect by the biotite granite which is assumed to be as a heat source in the area. Among the northern coast, some black shales in Uhangri and Mogsam areas which had been under the most moderate temperature environment snow symptomatic oily material, whereas, those in Sinseongri area do not, which were presumably to be intensive thermal alteration by the later acidic porphyries.

• 대기
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• 제33권1호
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• pp.49-59
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• 2023

Blocking refers to a class of weather phenomena appearing in the mid and high latitudes, whose characteristics are blocked airflow of persistence. Frequently found over the Pacific and Atlantic regions of the Northern Hemisphere, blocking affects severe weather in the surrounding areas with different mechanisms depending on the type of blocking patterns. Along with lots of studies about persistent weather extremes focusing on the specific types of blocking, a new categorization using Rossby wave breaking has emerged. This study aims to apply this concept to the classification of blockings over the Pacific and examine how different wave breakings specify the associated cold weather in the Korean peninsula. At the same time, we investigate a strongly developing ridge around the Pacific by designing a new detection algorithm, where a reversal method is modified to distinguish ridge-type blocking patterns. As result, Kamchatka blocking (KB) and strong ridge over the Central Pacific are observed the most frequently during 20 years (2001~2020) of the studied period, and anomalous low pressures with cold air over the Korean Peninsula are accompanied by blocking events. When it considers the Rossby wave breaking, cyclonic wave-breaking is dominant in KB, which generates low-pressure anomalies over the Korean Peninsula. However, KB with anticyclone wave breaking appears with the high-pressure anomalies over the Korean Peninsula and it generates the warm temperature anomaly. Lastly, the low-pressure anomalies are also generated by the strong ridge over the Central Pacific, which persists for approximately three days and give a significant impact on cold surge on the Korean Peninsula.

• 대기
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• 제19권4호
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• pp.345-370
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• 2009

Numerical experiments using the Weather Research and Forecasting (WRF) model were done to identify the role of the mountain ranges in the northern part of the Peninsula (referred as "the northern mountain complex"), in the occurrence of two heavy snowfall events over the Yeongdong region on 7-8 December 2002 and 20-21 January 2008. To this end, control simulations with the topography of the northern mountain complex and other simulations without the topography of the mountain complex were performed. It was revealed that the amount of snowfall over the Yeongdong region from the control simulation much more exceeded that of the simulation without the topography of the mountain complex. This increase of the snowfall amount over the Yeongdong region can be explained as follows: As the upstream flow approached the northern mountain complex, it deflected around the northern mountain complex due to the blocking effect of the mountains with a low Froude number less than ~0.16. This lead to the strengthening of northeasterly over the East Sea and over the Yeongdong region. The strong northeasterly is accompanied with much more snowfall over the Yeongdong region by intensifying air-mass modification over the sea and the orographic effect of the Taeback mountains. Thus, it was concluded that the topography of the northern mountain complex is one of the main factors in determining the distribution and amount of precipitation in the Yeongdong region when there is an expansion of the Siberian High toward the East Sea.

• 식물분류학회지
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• 제36권4호
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• pp.335-360
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• 2006

표본에 근거하여 한반도 야생란 88분류군에 대한 분포를 조사하고, 각 분류군의 분포도를 작성하였다. 한반도내 8개 식물 분포 아구에 분포하는 야생란의 분류군 수는 다음과 같았다; 갑산아구 27분류군, 관북아구 21분류군, 관서아구 13분류군, 중부아구 37분류군, 남부아구 39분류군, 남해안아구 33분류군, 제주도아구 64분류군, 울릉도아구 19분류군. 한반도 야생란의 72.7%가 제주도에 자라는데, 이 중 18분류군은 한반도에서는 제주도에만 분포한다. 한반도 야생란 중 30분류군은 상록활엽수림대에 자라며, 16분류군은 북부지역이나 고산에 분포하는 북방계 요소였다. 분포 조사를 기초로, 한반도 야생란을 국내에서 변형한 IUCN 적색 목록 범주에 따라 분류하였다. 절멸종(EX) 또는 야생에서의 절멸종(EW)에 속하는 난초과 식물은 한반도에서는 발견되지 않았다. 위급종(CR)에 속하는 분류군은 Cymbidium kanran(한란), C. lancifolium(죽백란), C. ensifolium(소란), Cypripedium japonicum(광릉요강꽃), Cyrtosia septentrionalis(으름난초), Dendrobium moniliforme(석곡), Habenaria chejuensis(제주방울란), H. radiata(해오라비난초), Neofinetia falcata(풍란), Sedirea japonica(나도풍란) 10분류군이었는데, 이 중 소란과 제주방울란은 이번 연구에서 처음으로 CR 범주로 기록되었다. 한편, 위기종(EN)으로 분류된 것은 22분류군으로, 이 중 Gastrochilus japonicum(탐라난), G. fuscopunctatus(금자란), Gastrodia verrucosa(한라천마), Habenaria flagellifera(방울난초), Herminium lanceum var. longicrure(씨눈난초), Chamaegastrodia sikokiana(애기천마), Lecanorchis kiusiana(제주무엽란), Neottia hypocastanoptica(한라새둥지란), Tipularia japonica(비비추난초)가 이번 연구에서 최초로 EN 범주에 포함되었다.

• 대기
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• 제23권4호
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• pp.527-538
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• 2013

In this study, climate over Korea based on the Historical scenario induced by HadGEM2-AO is simulated by WRF. For this purpose, a system that can be used be for numerical integration over the Far East Asian area of the center of the Korean Peninsula with 12.5 km-horizontal resolution was set-up at "Haebit", the early portion of KMA Supercomputer Unit-3. Using the system, the downscaling experiments were conducted for the period 1979-2010. The simulated results of HadGEM2-AO and WRF are presented in terms of 2 m-temperature and precipitation during boreal summer and winter of Historical for the period 1981~2005, compared with observation. As for the mean 2 m-temperature, the general patterns of HadGEM2-AO and WRF are similar with observation although WRF showed lower values than observation due to the systematic bias. WRF reproduced a feature of the terrain-following characteristics reasonably well owing to the increased horizontal resolution. Both of the models simulated the observed precipitation pattern for DJF than JJA reasonably, while the rainfall over the Korean Peninsula in JJA is less than observation. HadGEM2-AO in DJF 2 m-temperature and JJA precipitation has warm and dry biases over the Korean Peninsula, respectively. WRF showed cold bias over JJA 2 m-temperature and wet bias over DJF precipitation. The larger bias in WRF was attributed to the addition of HadGEM2-AO's bias to WRF's systematic bias. Spatial correlation analysis revealed that HadGEM2-AO and WRF had above 0.8 correlation coefficients except for JJA precipitation. In the EOF analysis, both models results explained basically same phase changes and variation as observation. Despite the difference in mean and bias fields for both models, the variabilities of the two models were almost similar with observation in many respects, implying that the downscaled results can be effectively used for the study of regional climate around the Korean Peninsula.

• 식물분류학회지
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• 제52권1호
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• pp.71-76
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• 2022

Tordylium maximum L. (Apiaceae), native to south, south-central Europe and southwest Asia and a rare alien plant in northern Europe, was newly found in Jeollabuk-do in Korea. Tordylium is clearly distinguished from other genera by having radiating petals, filiform bracts, linear bractlets, stalked mericarps with minutely vesicular dorsal face or strigose hairs, and an annual habit. Tordylium maximum is different from other species of the genus by its mericarps with smooth margins and 10-16 rays not contracted in fruit. T. maximum grows on dry and sunny grasslands. Here, we report the first occurrence of the genus Tordylium represented by T. maximum in Korea and provide a precise description, illustration, photographs of the species, and a taxonomic key to allied taxa in Korea.

• Journal of Species Research
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• 제11권1호
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• pp.29-37
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• 2022

This study is based on crane fly specimens collected more than 80 years ago in 1938-1939 and preserved at the United States National Museum, Smithsonian Institution, Washington DC, USA. Despite many attempts with a variety of methods, no additional specimens of this genus were captured. This likely means that that this genus is extinct on the Korean Peninsula, or its distribution is restricted to the northern areas of the Democratic People's Republic of Korea (North Korea). The genus Prionolabis Osten Sacken, 1860 with four species, one of them Prionolabis dis(Alexander, 1950) endemic to North Korea, was recorded by Ch. P. Alexander (Alexander, 1938, 1940, 1950). All succeeding papers listing these species were based on these original works without study based on actual specimens. For each species, we present general information on genus, redescriptions of species based on Korean specimens, illustrations of important taxonomical structures, elevation range, period of activity, habitat information, general distribution, and a distribution map for the Korean Peninsula.

• 지질공학
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• 제5권3호
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• pp.309-329
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• 1995

역사지진 카탈로그 즉, 1960년대 전과 이후 1995년까지의 지진관측을 이용하여 한반도의 지진활동과 응력상태가 연구되었다. 이씨왕조의 처음 1400-1600년대의 200년동안 역사지진 카탈로그는 크게 완성되었다. 그후부터 카탈로그는 거의 강진만 완성하는데 주력했다. 강진분포를 볼때 한반도 지진대는 서울-평양 지진대, 남부지진대, 그리고 북부지진대로 나눌 수 있다. 이들 강진의 초동 메카니즘은 그리드 테스팅 방법(grid testing method)에 의해서 재분석되었다. 지진메카니즘 결과는 압축방향이 동서방향을 따라서 수평으로 놓여 있음을 발견했다.