Research
Active Fault & Earthquake Hazard Assessment
Forces responsible for tectonic plate motions are accommodated by active faults.
The stored energy on active faults are released mostly by earthquakes.
I am trying to understand the history of paleo-earthquakes in a given active fault system, and its implications for earthquake hazard assessment.
Mapping Faults
· Large paleo-earthquakes resulted in ruptures on the Earth's surface, and this provides an opportunity to map the active faults.
· High-resolution fault mapping is an essential part for active fault study and seismic hazard assessment.
The HRS imagery mapping for the 1905 Bulnay earthquake surface rupture [Choi et al., 2018].
Fault Zone Architectures
· Internal structures of the faults are a result of repeated earthquakes, and they are able to affect to slip behaviors of the next earthquake.
· By studying fault zone architecture, it is possible to explore the evolutional history of the fault and to examine the characteristics of future earthquakes.
A cross-sectional fault zone model of the Yangsan Fault in Korea [Choi et al., 2009].
Continental Strike-Slip Earthquakes
· Continental strike-slip earthquakes are prone to major sources for seismic hazard.
· Fault geometry and slip variations along strike-slip earthquake surface ruptures are one of the most useful tools to study earthquake rupture processes.
· Fault segmentation plays a key role in understanding the history of earthquake ruptures both during individual events and over multiple events.
Geometry, slip distribution, and segmentation of the 1957 Gobi-Altay earthquake surface rupture [Choi et al., 2012]
Korean Active Tectonics
· Historical earthquakes in Korea have caused considerable damages, and yet I think we still have a poor map of active faults in the region.
· Korean active faults should be identified and studied in more detail based on high-resolution fault mapping and paleoseismology.
Segmentation of the Yangsan Fault in SE Korea [Choi et al., 2017].