Ramezan Ramezani Omali, Mehdi Saeidian, Naser Hafezimoghadas,
Volume 9, Issue 1 (6-2015)
Abstract
Determination of Faults activity rate is among the most important parameters of evaluating faulting hazards. In this paper, active faults on region of Shahid Rajai dam of Sari with radius 100 km based on fractal dimension of faulting and earthquake as well as evaluation of slip rate were classified and those Activity rate were assessed. In order to determine of fractal dimension of faulting and earthquake, Box-counting method was used. For estimate of slip rate beginning the seismicity parameters (a&b) of study area was estimation. Then these parameters were normalized for each fault. Based on the existing relationships and having a&b for each fault, the seismic moment of fault was calculated. Finally according to extant relations for evaluation of seismic moment rate, slip rate of each fault was determined and the faults of study area were classified accordingly. By grading based on fractal dimensions, the faults of North- Alborz, Damghan and Garmsar have been the most active faults in the study area during the last 100 years and according to evaluations of active rate of faulting and earthquake based on fractal dimensions, generally set in category BD and their activity approved. The faults with very low slip rate and with long return period of earthquake, are possible causes of occurrence large earthquakes (856 AD) Gomes and inducement fault namely Damghan Fault is an example of these faults. The faults of Astaneh, Rameh and Cheshmeh-ali have been low slip rate and thereupon be able to develop high seismic moment rate. According to earthquake events in privacy of New faults introduced (Khorram-abad, Majid,…), the high activity rate of these faults seem logical
