Spatiotemporal landslide detection for the 2005 Kashmir earthquake region

Various scientists forecasted long-term major slope failures after the 8 October 2005, 7.6 Mw earthquake in the northern parts of Pakistan along the Balakot–Bagh fault line. The earthquake-destabilized numerous slopes by creating a large number of tension cracks which may lead, together with the monsoonal climatic conditions, to increased landslide activity. To test these forecasts, an area of 36 km2 was selected in which changes in landslide activity, area, and types were quantified after each monsoon season for the following consecutive three years. On-screen stereo interpretations of high spatial resolution satellite imagery were carried out together with field investigations to identify landslide types and to quantify their changes in the area. The landslide inventory showed that 158 landslides were triggered along the Balakot–Bagh fault line. The most abundant type of active landslide was translational, which was mainly concentrated along the fault line in the Muzaffarabad Formation. Landslide activity was very high for a period of two-years at maximum, after which the majority of the slopes gained a state of stability. In contrast to the predictions of long-term extensive landslide activity, slopes started re-vegetating and landslide activity decreased within two years after the earthquake.