A penultimate great earthquake revealed by in situ cosmogenic 10Be dating of the bedrock fault surface on the Huashan Piedmont Fault (Central China)

Obtaining strong earthquake recurrence parameters through paleo-earthquake studies is crucial for analysing and assessing the future strong earthquake hazard of active faults. This study reconstructs the seismic history of the Huashan Piedmont Fault using in situ cosmogenic 10Be exposure dating of bedrock fault surface. By analysing 10Be concentrations and exposure ages from the Duyu bedrock fault surface, this research identifies a penultimate great earthquake event, establishes its age and co-seismic displacement and calculates the fault's Late Holocene vertical slip rates. The study provides new insights into the revealing great paleo-earthquakes on the Huashan Piedmont Fault, contributing to seismic risk assessment in the Weihe Basin, a densely populated region in central China. We believe that our study makes a significant contribution to the literature because it demonstrates the feasibility and effectiveness of using cosmogenic 10Be nuclide exposure dating to reconstruct paleo-earthquake histories on normal faults containing quartz, particularly in areas with dense vegetation and human activity where conventional trenching methods are challenging. This approach not only fills a gap in understanding the seismic history of the Huashan Piedmont Fault but also offers a novel methodology applicable to similar seismogenic structures worldwide.