Deformation rate in a compressional tectonic setting derived from Monte Carlo simulation

Deformation rate is an important parameter to constrain the strength of tectonic activity. An accurate and reliable constraint is one of the main aims of tectonic geomorphology and active tectonics research. In this paper, taking river terrace as the reference, the vertical slip rates of the Hutubi Fault in the northern piedmont of the Tianshan Mountains and the Minle-Damaying Fault in the northern piedmont of the Qilian Shan in the Tibet Plateau are redefined by the Monte Carlo simulation. The results show that the Holocene slip rates of the Hutubi Fault and the Minle-Damaying Fault are 0.39+0.04/-0.03mm/a and 0.9+0.08/-0.07mm/a, respectively. Based on the ratio of the amount and timing of deformation, the slip rate of the Hutubi Fault is determined to 0.34~0.40mm/a. By a linear regression method using the amount and timing of deformation, the slip rate of the Minle-Damaying Fault is estimated to 0.9±0.2mm/a. These above rates show that the Monte Carlo simulation method can give a better constraint on the deformation rate. Today, the high-precision topography is available and the dating method has been significantly improved. These progresses are helpful for better constraining the rate of deformation. If a reliable deformation rate can be obtained, the matching relationship between the deformation amount and age of the fault needs be paid attention to. From the perspective of simulating a reasonable fault slip history, the Monte Carlo simulation can make the estimation of the deformation rate more accurate, which can provide more useful foundational information for the seismic risk assessment.