[SSS12-P19] Active tectonics around an ongoing rapid surface deformation area in southern Taiwan by integrating geodesy and field investigation
Keywords:PS-InSAR, Interseismic deformation, Meinong earthquake
Mudstone areas in southern Taiwan are located at the frontal fold-thrust belt of the Western Foothills. They are one of the areas with the most active surface movement and rapid topographic evolution in Taiwan. In the past century, there were more than ten disaster earthquakes in southwestern Taiwan. The M 6.6 Meinong earthquake occurred on February 5, 2016 and generated surface rupture along two lineaments near the town of Guanmiao. However, these two structures were neither well documented before nor included in structural models. In addition, the Lungchi area right east of the two lineaments shows both rapid preseismic and coseismic deformation, raising a question if this area is sensitive to stress change or the deformation is just transient. Therefore, this study aims to create a new active structural fault model in this region. We integrate observations from PS-InSAR and GPS to constrain short-term active tectonic patterns and the interseismic deformation rates. Moreover, we map river terraces based on field investigations along the upstream of Erren River to estimate long-term deformation patterns and rates. Thus, we can provide a new model of active tectonic and seismic potential in this area.