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Reconstructing and quantifying fault slip is essential for better understanding of the dynamics of faulting and seismic hazard assessment (Avouac, 2015;Harris, 2017). Distinguishing and estimating seismic or aseismic fault slip on geologic timescales (specifically ∼10 1−4 years) is challenging due to the lack of historical, geodetic, remote sensing data extending beyond a few decades or centuries. Moreover, seismic or aseismic slip record in landform and sedimentary archives over such timescales is often incomplete because geologic processes, including later earthquakes, which may destroy the evidence of earlier earthquakes (McCalpin & Nelson, 2009). However, bedrock fault scarps provide one of the best archives for studying past earthquakes and determining the nature and rates of fault slip because they are resistant to erosion and relate directly to a particular fault.Over the past few decades, exposure histories of bedrock fault scarps have been inferred by methods based on the accumulation of terrestrial cosmogenic nuclides (TCNs; Williams et al., 2017;Zreda & Noller, 1998). However, these methods have significant challenges for earthquakes with short recurrence intervals that lay within the uncertainty of the dating and the difficulties of measuring the extremely low concentrations of TCNs in young (10 1−2 years) bedrock fault scarps (Zreda & Noller, 1998). Moreover, it is hard to distinguish discontinuous points in the profiles of TCN concentration versus fault scarp height because the fault displacements for some