• Journal of the Earthquake Engineering Society of Korea
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• v.4 no.1
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• pp.13-34
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• 2000

본 연구에서는 서기 2년부터 1977년까지 남.북한 역사지진(A.D 2-1904)과 초기 계기 지진(1905-1977) 목록을 이용하여 남한 지진 규모로 재조정된 지진목록을 작성하였다 역사 지진은 과거의 협소한 인구분포로 인해 지진 기록의 누락이 많앗다 지진 위험도를 작성하기 위해 지진 발생분포와 지체구조의 특성을 고려하여 4개의 지진구(seismic province)를 설정하였다. 각 지진구에서 최대 잠재 지진결정은 Gumbel의 최대치 이론을 이용하였다 제 1수정 점근 함수 분포에서 유한 상한 값(finte upper boundary) 의 존재는 각 지진구에서 발생할 최대 잠재 지진의 진원(source)이 유한하다는 사실과 잘 일치한다. 따라서 이를 근거로 각 지진구에서 10년 , 20년, 30년, 50년 이내에 2% 5% 10% 초과 확률을 갖는 최대 규모지진을 추정하였다 또한 각 지진구에서 유한 지진원은 과거에 발생했던 큰 규모의 특정 지진과 지진 지체구조 정보에 근거하여 결정하였다. 연구결과 조선시대(1392-1904) 의 지진위험도에서는 경주 울산지역과 서울과 평양지역을 따라 높은지반 가속도 값을 보이며 경주지역에서 0.24g의 최대 지반 가속도 값으로 나타났다 계기 지진목록(1905-1998)을 이용한 한반도의 지진 위험도에서는 경주, 울산, 대구 지역에서 0.10-0.12g 의 최대 지반가속도 값을 보였다. 그리고 계기 지진 목록(1905-1998) 만을 이용하여 작성한 서울.경기 지역의 지진 위험도에서는 김포, 잠실 , 성남 지역의 한강을 따라 분포하는 충적층과 강남지역의 지반 운동이 한강 이북의 대보 화강암 지역에 비해 비교적 높은 0.09-0.10g의 지반 가속도를 보이는 것이 특징이다.

• Journal of the Korean Geophysical Society
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• v.3 no.4
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• pp.261-268
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• 2000

Minimum magnitudes $(M_c)$ for estimation of seismicity parameters were analyzed for the earthquake catalog of Korea Meteorological Agency (KMA). The temporal variation of earthquake frequency suggests that a proper $M_c$ be 3.0 for the whole southern part of the Korean Peninsula. The b-value with $M_c$ of 3.0 is estimated to be 1.11, which is larger than those of the previous studies. To see the spatial variation of $M_c$, the southern part of the peninsula were divided into grids of $0.1{\times}0.1$ degree. At the greater portion of grid points, the local earthquake catalogs do not satisfy given statistical criteria. The grid points whose local earthquake catalogs meet the criteria mostly distribute in the eastern part. $M_c$ at these points range 2.4 to 3.5 and b values range 0.75 to 1.73 with the average of 1.08 which is comparable to that for the whole southern part of the peninsula.

• Proceedings of the Korean Nuclear Society Conference
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• 2001.10a
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• pp.341.1-341
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• 2001

• Journal of the Korean Geophysical Society
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• v.7 no.3
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• pp.185-192
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• 2004

We calculate moment magnitudes of earthquakes occurred in the southern part of the Korean Peninsula from January, 2001 to February, 2004 and compare them with local magnitudes published by KMA(Korea Meteorological Administration) and KIGAM(Korea Institute of Geoscience and Mineral Resources). From this study, we find that local magnitudes of KIGAM have higher correlation with moment magnitudes than local magnitudes of KMA have. We induce a proper conversion formula by analyzing relation between published local magnitudes and calculated moment magnitudes. The induced formula can be used to unify kinds of magnitudes in earthquake catalogues and unified earthquake catalogues can be applied as necessary factors for analyzing earthquake characteristics, seismic hazards or attenuation formulas in the southern part of the Korean Peninsula.

• Explosives and Blasting
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• v.18 no.3
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• pp.83-88
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• 2000

국내 지진관측소로부터 분석된 지진기록에는 자연지진 이외의 상당수의 인공발파를 포함하는 것으로 해석된다. 자연지진에 대한 지진특성연구, 지질학적 지진의 진원지연구 등을 위 해서는 지진목록에서 인공발파를 식별할 필요가 있다. 한국자원연구소는 인공발파 식별을 위한 연구의 일환으로 지진-공중음파 관측망을 운영 중에 있다. 지진-공중음파 자료분석으로 구분된 인공발파 기록의 대부분이 발파를 실시하는 산업현장과 일치하고 있음이 확인되었다. 발파장의 위치, 발파시간, 규모 및 발파방법 등의 정보는 공중음파를 이용한 인공발파 식별에 관한 정량적 연구와 자연지진에 관한 연구 등에 기본적인 정보(Ground Truth Database)를 제공하리라 판단되므로 국내에서 실시되는 인공발파에 대한 정보가 요구된다.

• Proceedings of the Korean Nuclear Society Conference
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• 1999.05a
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• pp.426-426
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• 1999

• The Korean Journal of Applied Statistics
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• v.30 no.5
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• pp.759-774
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• 2017

Earthquake concerns have grown after a remarkable earthquake incident on September 12th, 2016 in Gyeongju, Korea. Earthquake forecasting is gaining in importance in order to guarantee infrastructure safety and develop protection policies. In this paper, we adopt a power-law distribution model to fit past earthquake occurrences in Korea with various historical and modern seismological records. We estimated power-law distribution parameters using empirical distributions and calculated the future probabilities for large earthquake events based on our model. We provide the probability that a future event has a larger magnitude than given levels, and the probability that a future event over certain levels will occur in a given period of time. This model contributes to the assessment of latent seismological risk in Korea by estimating future earthquake probabilities.

• Journal of the Korean Geophysical Society
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• v.1 no.1
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• pp.3-22
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• 1998

Korea boasts of abundant historical earthquake records of almost 1900 events. The epicenters and intensities of these earthquakes are determined on the basis of descriptions and felt areas of the events. It turns out that most of the earthquakes occurred on major faults or tectonic boundaries of the peninsula except for the northeastern part which had been the least disrupted by tectonic disturbances during the Mesozoic. It appears that the crustal layers of the southern and northwestern parts of the peninsula had been severely ruptured during the Mesozoic disturbances and some of the faults thus generated have been active since. The seismicity of the peninsula had been rather low from the first to the fourteenth century, but unusually high from the fifteenth to the eighteenth century, and have been rather low since. This period of unusually high seismicity of the peninsula coincides with that of the northeastern part of China, suggesting the two areas are seismologically closely connected. It appears that most of the seismicity of the peninsula results from the high stress propagating from the Himalayas where the Eurasian and Indian plates collide. The data file of Korean historical earthquakes is not yet complete and supplementary studies are under way. The main purpose of this paper is to provide the data file of Korean historical earthquakes analyzed up to date for geoscientists and engineers in need of this file.

• The Journal of Engineering Geology
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• v.2 no.2
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• pp.147-154
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• 1992

A computer simulation of earthquake sequence in the time and magnitude space was done using random number generation. The theory of the simulation are based on the two statistical models of earthquake events. Those models are Stationary Poisson Process for independent earthquakes and Branching Markov Process for aftershocks. The generated earthquake sequnces resemble the actual earthquake catalogs.

• The Journal of Engineering Geology
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• v.5 no.1
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• pp.45-58
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• 1995

A probabilistic seismic risk in the Korean Peninsula is calculated from the instrumental eaathquake data. For the purpose, an instrumental earthquake catalogue since 1905 m which parameters are readjusted to have uniformity and homogeneity in description is cornpiled through the review of all available data. The maximum potential earthquake expected in the Korean Peninsula for 100, 1000, and 4000 years are estimated to be 6.3, 7.2 and 7.8 in magnitude, respectively, from Gumbel's extreme value theory. In addition, contour rnaps representing the maximum ground acceleration expected for 100 and 1000 years are prepared using the return period method. Seismic hazart] curves in which maximum ground acceleration expressed in terms of probability of occurrence are also presented for the major populated areas.