Earthquake Mechanism of Korean Peninsula

한반도 지진의 메카니즘 특성

In and around the Korean Peninsula 22 intraplate earthquake mechanisms since 1936 were analyzed to understand the regional stress orientation and tectonics. These 22 earthquakes are largest ones in this century and may represent the characteristics of earthquake in the region. Focal mechanism of earthquakes in the region show predominant strike-slip faulting with small amount of thrust components. The average P-axis is almost horizontal ENE- WSW. Studied data are compared with neighboring intraplate region in order to understand the tectonic regime in far est Asia. In northeastern China strike-slip faulting is dominant and nearly horizontal average P-axis in ENE- WSW is very similar with the Korean Peninsula. On the other hand in the eastern part of East Sea thrust faulting is dominant and average P-axis is horizontal with ESE- WSW This indicate that not only the subducting Pacific Plate in east but also the indenting Indian Plate controls earthquake mechanism in the far east of the Eurasian Plate.