Proceedings of the 12th International INQUA meeting on paleoseismology, active tectonic and archaeoseismology

records, there is a demand for active fault mapping and paleoseismic studies in Korean peninsula more specially in central part of Korea where such studies are very sparse (Kim et al., 2023; Lee et al., 2023). In slow tectonic regions, where earthquakes generally have long recurrence intervals, coseismic landforms are often modified over time. Therefore, multiple techniques such as vintage aerial photos, previous aerial photos, high-resolution LiDAR DEM, and high-resolution geophysical methods are needed. We have used all these tools to identify right-lateral offsets resulting from active faulting along the Yeongdong Fault (YF) and to carry forward detailed paleoseismic studies. This highlights the usefulness of LiDAR DEM and ERT in identifying active faults in very slow tectonic settings (Choi et al., 2015; Marliyani et al., 2016; Diercks et al., 2023; Naik et al., 2024). As mentioned in the trench section description, the age range in Unit 20 is anomalous within a single depositional layer. Crude bedding within the layers, clasts predominantly derived from bedrock, and the high slope area indicate that the sediment source is located near the trench. A likely explanation for the age gap within Unit 20 is the disturbance of the parent material. Since quartz grains derived from metamorphic rocks exhibit inherently higher OSL sensitivity (Sawakuchi et al., 2011), we suggest that the age of Unit 20 is closer to >44 ± 3 ka and >53 ± 8 ka. Considering the age of the capping unit it is inferred that the latest faulting event occurred between 53 ± 8 ka to 11.0 ± 0.4 ka. This present paleoseismological study suggests that the YF is active during late Pleistocene. This present study can combine with other paleoseismological studies along central Korea (Kim et al., 2022; Lee et al., 2023) for a better understanding the timing of past earthquakes. Also this finding can be incorporated in the existing seismic hazard assessment studies for the central Korean Peninsula. A C K N O W L E D G M E N T S This work was supported by the Korea Institute of Energy Technology Evaluation and Planning (KETEP) and the Ministry of Trade, Industry & Energy (MOTIE) of the Republic of Korea (No. 20201510100020) and by grant (2022-MOIS62-001(RS- 2022-ND640011)) of National Disaster Risk Analysis and Management Technology in Earthquake funded by Ministry of Interior and Safety (MOIS, Korea).