2007 Volume 2 Issue 2 Pages 72-85
After the Mw 7.6 2005 Pakistan earthquake, we interpreted the CORONA satellite photographs in the earthquake-hit area to recognize the causative fault. We found a 66 km-long NW-SE striking thrust fault with right-lateral slip components. Because the focal mechanism of the earthquake matched the characteristics of the active fault from the view of its location, strike and slip sense, and also the fieldwork revealed the surface rupture followed the trace of the fault at a lot of places, the fault must be responsible for the 2005 Pakistan earthquake. The middle part of the fault accords with the 16 km-long Tanda fault found by Nakata et al. (1991), however we newly named the fault related to the earthquake as Balakot-Garhi fault by taking names of the major town near the terminus of the fault. According to an empirical theory between the geometric pattern of fault's bifurcation and direction of the rupture propagation, the rupture along the fault might propagate from around Muzaffarabad to its both ends, which is concordant with the rupture process of the earthquake. Based on comparison between the satellite imageries before and after the earthquake, the slope failures triggered by the earthquake were concentrated around Muzaffarabad close to the epicenter, and in the hanging side of the fault within 5 km width from the fault trace.
