Strain accumulation in South Korea inferred from GPS measurements

Monitoring the variation of the crustal strain is a key issue to understand the physical process of crustal tectonic activities. In this paper, GPS data for the period from March 2000 to February 2004 were analyzed to quantitatively investigate the plate deformation patterns and distributions in the South Korean peninsula. The results show two anomalous rates of strain accumulation in South Korea, a W-E compression accumulation of crustal strain in the East and West parts, and a N-S extension strain accumulation in the middle part along the longitude of about 127.5°E. In addition, the GPS-derived seismic moment accumulation rate is significant and consistent with recent historic earthquakes and fault zones in South Korea. The most anomalous seismic moment rates are in the middle part (about 127.3°E, 35.5°N), North edge (about 128.0°E, 38.0°N) and Northeast part (about 128.5°E, 37.3°N) of South Korea, indicating a high earthquake risk.