• Journal of the Korean Geophysical Society
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• v.3 no.2
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• pp.91-98
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• 2000

The seismicity of the Korean Peninsula shows a very irregular pattern of strain release typical of the intraplate seismicity. The Korean Peninsula may be divided into several tectonic provinces of differing tectonics. In this analysis, seismicity parameters for each tectonic province are evaluated from historical as well as instrumental earthquake data of the Korean Peninsula to examine the differences in seismic characteristics among tectonic provinces. Statistical analysis of the earthquake data made of incomplete data before the Choseon Dynasty and complete data afterwards reveals that there exist no significant differences in seismic characteristics between the tectonic provinces. It turns out the b-value in the intensity-frequency relation for the whole peninsula is about 0.6 and the maximum earthquake is about MMI X. The results of this study may be used in the probabilistic seismic hazard analysis of the Korean Peninsula and in estimating the design earthquake in earthquake engineering.

• Economic and Environmental Geology
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• v.13 no.1
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• pp.51-63
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• 1980

The seismicity of the Korean Peninsula and its vicinity is investigated temporally (2 A. D. to 1978) and spatially to evaluate the seismic risk and to understand the neotectonics around the peninsula. The study has been conducted using macrocosmic data obtained from historical literature, and instrumental records recorded by the Worldwide Network of Standardized Seismographs(WWNSS). The seismicity of the peninsula was active from the 13th through the 17th centuries. A seismic quiescence began at the onset of the 18th century, and has continued for the last 200 years. Presently, the seismicity region is found to be active again. The return periods are determined by a statistical method based upon the cumulative magnitude recurrence. They indicate that the seismic risk is greater in the south or west than in the north or east of the peninsula. Focal mechanism solutions demonstrate that the neotectonic stress distribution in the Japan Sea is greatly influenced by the subduction of the Pacific Plate under the Eurasian Plate or the Philippine Sea Plate, even though the predominate local paleotectonics is controlled by the spreading of the earth's crut.

• 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.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1997.04a
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• pp.3-14
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• 1997

• Proceedings of the KSEEG Conference
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• 2003.04a
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• pp.123-130
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• 2003

어떤 지역에서 발생가능한 지진동을 확률적으로 예측하기 위해서는 그 지역을 포함한 광범위한 지역의 지진원(seismic source zone)을 정의하지 않으면 안된다. 지진원이란 동일한 지진학적, 지체구조적, 지질학적 양상을 가지는 지역을 의미하며, 지진활동이 지역내에서 균질로 하나의 지진규모 - 발생빈도 관계식에 의해 표현될 수 있는 지역으로 가정된다. 또한 하나의 지진원 내의 지진활동성은 그 지역 전반에 걸쳐 고르게 분포하고 미래의 지진은 그 지역내의 어떠한 곳에서도 발생할 수 있다고 가정된다. (중략)

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1999.04a
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• pp.27-31
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• 1999

진도의 거리에 따른 감쇠양상은 두가치 측면에서 중요하다. 첫째는 역사지진의 크기를 평가하는데 사용되고 둘째는 역사지진자료를 이용하여 지진위험도를 평가하는데 이용된다. 한반도의 경우 대부분의 지진활동 자료가 역사지진이므로 이지진들의 크기를 결정하고 이들을 이용하여 지진위험도를 평가하기 위하여 합리적인 진도감쇠양상의 결정은 매우 중요한 과제라 할수 있다 진도의 감쇠양상은 진앙진도와 진앙거리 등 두요소에 같이 의존함이 알려져 있으므로 한반도에서 MMI VIII만의 지진자료를 이용하여 결정된 Lee의 기존의 감쇠공식은 그 사용범위에 한계가 불가피하므로 상기 두 가지 요소를 함께 고려한 새로운 감쇠공식의 유도가 요구되어진다. 지체구조적으로 Sino-Korean 지괴라고 불리우는 중국 북동부와 한반도에서 발생한 MMI VIII-X 지진들의 자료를 이용하여 한반도에서 발생하는 MMI VIII-X의 강진들에 대한 새로운 진도감쇠양상을 결정하였다.

• The Journal of Engineering Geology
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• v.5 no.3
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• pp.309-329
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• 1995

Seismicity and stress state in the Korean peninsula are studied using the catalogue of historical earthquakes and that from the seismological observations before the 1960s, with the aid of instrumental catalogue up to 1995. It seems that the completeness of the historical catalogue has a significant enhancement during the first two hundred years of the Yi dynasty, i.e., from the 1400s to the 1600s. From then on the catalogue may be regarded as near to complete for strong earthquakes in an overall sense. From the distribution of strong earthquakes, three seismic zones may be identified. From the south to the north, those are the southern seismic zone (남부지진대), the Seoul-Pyongyang seismic zone (서울-평양지진대), and the northern seismic zone (북부지진대). The mechanisms of some earthquakes obtained using first motion read- ings are reevaluated with a grid testing method. The results indicate that the compressional axis is nearly horizontal along the EW direction.

• Geophysics and Geophysical Exploration
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• v.13 no.3
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• pp.256-267
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• 2010

Earthquakes in the Korean Peninsula occur along the faults formed and boundaries between major geological units ruptured due to violent tectonic activities during the Mesozoic. E-W and/or ENE-SSW compressive stress regime resulting from collisions between the Eurasian plate and neighbouring the Indian plate, the Pacific plate and the Philippine plate trigger Korean earthquakes of thrust faulting with predominant strike-slip components along the mostly NNE-SSW trending active faults. Seismicity of the Korean peninsula has been moderate to low during the past 20 centuries except for the period from the 15th to the 18th centuries of exceptionally high seismicity, showing the typical irregularity of intraplate seismicity. The structure of the Korean peninsula is rather homogeneous without the Conrad discontinuity sharply dividing the upper and lower crust. Lateral heterogeneities exist in the crust. The crust with an average thickness of about 33 km is thicker in the mountainous region than the plain due to the Airy-type isostatic equilibrium maintained in the peninsula. Crustal P-wave velocity with average of about 6.3 km/sec increases gradually from the near surface to the Moho. The upper mantle P-wave (Pn) velocity is about 7.8 km/sec.

• KIPS Transactions on Software and Data Engineering
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• v.12 no.11
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• pp.493-504
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• 2023

The Republic of Korea is located far from the boundary of the earthquake plate, and the intra-plate earthquake occurring in these areas is generally small in size and less frequent than the interplate earthquake. Nevertheless, as a result of investigating and analyzing earthquakes that occurred on the Korean Peninsula between the past two years and 1904 and earthquakes that occurred after observing recent earthquakes on the Korean Peninsula, it was found that of a magnitude of 9. In this paper, the Korean Peninsula Historical Earthquake Record (2 years to 1904) published by the National Meteorological Research Institute is used to analyze the relationship between earthquakes on the Korean Peninsula and statistical self-similarity. In addition, the problem solved through this paper was the first to investigate the relationship between earthquake data occurring on the Korean Peninsula and statistical self-similarity. As a result of measuring the degree of self-similarity of earthquakes on the Korean Peninsula using three quantitative estimation methods, the self-similarity parameter H value (0.5 < H < 1) was found to be above 0.8 on average, indicating a high degree of self-similarity. And through graph visualization, it can be easily figured out in which region earthquakes occur most often, and it is expected that it can be used in the development of a prediction system that can predict damage in the event of an earthquake in the future and minimize damage to property and people, as well as in earthquake data analysis and modeling research. Based on the findings of this study, the self-similar process is expected to help understand the patterns and statistical characteristics of seismic activities, group and classify similar seismic events, and be used for prediction of seismic activities, seismic risk assessments, and seismic engineering.

• Magazine of the Korea Concrete Institute
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• v.9 no.1
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• pp.4-12
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• 1997