RELATIONSHIPS BETWEEN EARTHQUAKE MAGNITUDES AND GEOLOGICAL PARAMETERS: A CASE STUDY ON THE SE KOREAN PENINSULA

The evaluation of the maximum potential earthquakes and surface displacements from seismic sources plays a significant role in the seismic design of the major industrial facilities and structures located on or near the sources. To estimate the maximum potential earthquakes and surface displacements from the seismic sources, we need to characterize the geological parameters of expected seismic sources including slip type, slip rate, earthquake return period, ruptured area, surface rupture length, fault geometry, etc.

Especially in the case of the southeastern(SE) part of Korean peninsula, it has been recently debating whether some of the Quaternary faults near major industrial facilities such as the nuclear power plants are capable faults or not. If the facilities exist near the capable faults, evaluation of maximum potential earthquake and surface displacements from the faults is one of the most important issues in the seismic hazard analysis for the facilities. However, because the historical earthquake records and the geological parameters of the seismic sources are mostly limited, it is actually very difficult to estimate the maximum potential earthquakes and surface displacements from the sources, and to ensure the deterministic seismic safety of the facilities and structures.

In this paper, we review the various empirical methods for the potential earthquakes from fault parameters such as fault displacement, slip rate, rupture length, etc. and discuss the most reasonable methods on estimation of maximum potential earthquakes for the seismic design in Korea. We also review on the application of the Probabilistic Fault Displacement Hazard Analysis (PFDHA) which has recently been applying to the seismic hazard analysis.