Landslide Assessment Along the Karakoram Highway, Pakistan

The study was directed along the KKH, which passes through the districts of Gilgit, Hunza, and Nagar of Gilgit Baltistan, Pakistan. This research focuses on a significant section of the KKH, which has a total length of 332 km and includes a 10 km buffer zone (Fig. 1). The study region covers an area of 3320 km². The research region consists of a chain of villages through which the KKH passes, beginning with Juglot, and ending with Khunjarab top, the China–Pakistan border checkpoint. The region's terrains are rough, ranging from 1211 to 7831 metres above mean sea level. Structurally, the region is complex because it lies in the subduction zone (Main Karakoram Thrust).Figure 1

A map showing the study region; (a) Pakistan's geographic map representing district boundaries; (b) a map of Pakistan showing its geographical boundaries; and (c) a Digital Elevation Model of Gilgit Baltistan where points show Landslides of the study region, and the black line shows the KKH.

Moreover, the mountains have steep slopes that are prone to landslides⁴³ . The research region's most common landslides are debris, and rock falls induced by precipitation and seismic activity^{6 (link)}. Most of the rocks are Mesozoic and Paleozoic in age. The majority of the region's exposed rocks are volcanic, volcano-sedimentary, metamorphic, sedimentary, and igneous. These rocks are divided into siliciclastic, basalt, carbonates, andesite, gabbro, granite, greenschist and so on.
Gilgit Baltistan has around 154 mm of rain each year. Water irrigation for land cultivation is supplied by rivers and streams overflowing with snowmelt and glacial water from mountainous regions. Summer is more prolonged, drier, and hotter. Strong sunlight occasionally elevates temperatures beyond 40 °C (104 °F), although the winter's average temperature remains below 10 °C. There are numerous landslides and avalanches in the region due to the harsh weather conditions^{44 (link)}. The region's geological traits and soils, which also play a crucial role, are fragile.