Abstract:The Weihe Basin, which is situated in the middle of China, was the area of interest for this study. The basin is several hundred kilometers long and forms an S-shape, representing a deep rift that divides China into eastern and western parts. Bounded by the Ordos, North China, and South China blocks, the Weihe Basin is the accommodation zone for the differential motion of these three blocks and also the border and decoupled strip of tectonics between western and eastern China. We simulated the deformation state of the main fault slip and rotation in the Weihe Basin using a combined disclination-dislocation model. The horizontal displacements caused by fault slip and rotation were acquired through numerical calculation and compared with GPS-measured horizontal displacements in the Weihe Basin. The results were as follows.(1) The movements of fault slip and rotation can be described well by the combined disclination-dislocation model, and there are only small differences between the modeling results and monitoring data.(2) Use of only the dislocation model does not adequately describe the activity features of the faults within the Weihe Basin that show slip and rotation, and there are significant differences between the model results and monitoring data, particularly in the direction of crustal movement.(3) Compared to the dislocation model, there is good consistency between the simulated horizontal displacements of the combined model and the measured GPS results.
