Examining the regularity in slip over seismic cycles leads to an understanding of earthquake recurrence and provides the basis for probabilistic seismic hazard assessment. Systematic analysis of three-dimensional paleoseismic trenches and analysis of offset markers along faults reveal slip history. Flights of displaced terraces have also been used to study slips of paleoearthquakes when the number of earthquakes contributing to the observed displacement of a terrace is known. This study presents a Monte Carlo-based approach to estimating slip variability using displaced terraces when a detailed paleoseismic record is not available. First, we mapped fluvial terraces across the Kamishiro fault, which is an intra-plate reverse fault in central Japan, and systematically measured the cumulative dip slip of the mapped terraces. By combining these measurements with the age of the paleoearthquakes, we estimated the amount of dip slip for the penultimate event (PE) and antepenultimate event (APE) to be 1.6 and 3.4 m, respectively. The APE slip was nearly three times larger than the most recent event of 2014 (Mw 6.2): 1.2 m. This suggests that the rupture length of the APE was much longer than that of the 2014 event and the entire Kamishiro fault ruptured with adjacent faults during the APE. Thereafter, we performed the Monte Carlo simulations to explore the possible range of the coefficient of variation for slip per event (COVs). The simulation considered all the possible rupture histories in terms of the number of events and their slip amounts. The resulting COVs typically ranged between 0.3 and 0.54, indicating a large variation in the slip per event of the Kamishiro fault during the last few thousand years. To test the accuracy of our approach, we performed the same simulation to a fault whose slip per event was well constrained. The result showed that the error in the COVs estimate was less than 0.15 in 86% of realizations, which was comparable to the uncertainty in COVs derived from a paleoseismic trenching. Based on the accuracy test, we conclude that the Monte Carlo-based approach should help assess the regularity of earthquakes using an incomplete paleoseismic record.

检查地震周期滑移的规律性有助于了解地震复发，并为概率地震灾害评估提供基础。三维古地震沟槽的系统分析和沿断层的偏移标记的分析揭示了滑动历史。当已知导致梯田位移的地震次数已知时，也可以使用流离失所的梯田的飞行来研究古地震的滑动。这项研究提出了一种基于蒙特卡洛的方法，用于在没有详细的古地震记录时使用位移阶地估算滑移变化率。首先，我们绘制了横跨Kamishiro断层的河流阶地，该岩层是日本中部的板内逆断层，并系统地测量了所绘制阶地的累计倾滑量。通过将这些测量值与古地震的年龄相结合，我们估计倒数第二个事件（PE）和倒数第二个事件（APE）的倾滑量分别为1.6 m和3.4 m。APE滑移几乎是2014年最新事件（Mw 6.2）：1.2 m的三倍。这表明APE的断裂长度比2014年的断裂长度要长得多，整个Kamishiro断裂在APE期间因相邻的断裂而断裂。此后，我们进行了蒙特卡洛模拟，以探索每个事件的滑差（COV）的变化系数的可能范围。模拟根据事件的数量及其滑移量考虑了所有可能的破裂历史。产生的COV通常在0.3到0.54之间，表明过去几千年来Kamishiro断层每次事件的滑动差异很大。为了测试我们方法的准确性，我们对故障进行了相同的仿真，该故障的每个事件的滑动性受到了很好的约束。结果表明，在86％的实现中，COV估计的误差小于0.15，这与古地震开挖产生的COV的不确定性相当。基于准确性测试，我们得出结论，基于蒙特卡洛的方法应有助于使用不完整的古​​地震记录来评估地震的规律性。这与古地震ose沟产生的COV的不确定性相当。基于准确性测试，我们得出结论，基于蒙特卡洛的方法应有助于使用不完整的古​​地震记录来评估地震的规律性。这与古地震ose沟产生的COV的不确定性相当。基于准确性测试，我们得出结论，基于蒙特卡洛的方法应有助于使用不完整的古​​地震记录来评估地震的规律性。