During the last two decades, the South part of Fars seismotectonic zone of Zagros has been active. The Zagros seismotectonic belt consist of a series of fault-related folds that seismic areas and hydrocarbon reservoirs have been formed, related to their evolution. Although characteristics of Zagros are good known, the distribution of active deformations, style of fault-related folds, and its seismotectonic behavior are among the features that require further investigation.
In this study, changes in seismic rate based on changes in seismic parameter (b-value) and fractal dimension of seismicity (D-value) have been investigated using instrumental seismic data in the period 2000 to 2021. Total amount of b-value and D-value was calculated by the least square’s method and the correlation integral method respectively and the map of these parameters was plotted by interpolation method.
decrease of b-value in northeastern of study area indicates that stress is increasing, which may signal a future sizable earthquake. Also, the spatial variation of b suggests that the SW segment is less stressed compared to the NE segment. Considering that the correlation coefficient is about-0.78. So, the probability of occurrence of large earthquakes on large area faults increase. The b-value/D-value parameter zoning map found valuable information on the invariance property of the seismic variation scale in the area. These results suggest that this approach can be used as a useful tool to evaluate seismic power distribution on seismotectonic active regions.
According to the zoning maps and the identification of high stress zone in the study area, the north parts of MFF, surrounding of Jam, surrounding area of Jam, Farashband and in the later stages Khormuj cities will be introduced as the main candidate areas for future earthquakes. Baghan plain is located in the relatively high-risk area in this study.
Also, it seems that oscillation of ground water level in the selected wells in the Bgha