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FEATURE ARTICLE

Gifts and Perils of Landslides

Catastrophic rockslides and related landscape developments are an integral part of human settlement along upper Indus streams

Kenneth Hewitt

Landslide Villages

2010-09HewittF9.jpgClick to Enlarge ImageThe village of Gol on the Indus is a typical oasis of human-made greenery amid bare rock walls, closely adapted to features developed after a landslide descended from nearby mountain walls. In fact, debris from two megaslides blocks the Indus here for 11 kilometers. Most of the way it forms barren, boulder-covered terrain used, much like Ghoro Cho, for seasonal grazing and hunting, and where shepherds gather great bales of Artemesia for kindling. Gol itself is on a rock avalanche lobe that travelled 5 to 6 kilometers up the valley. Boulder-covered mounds support homes and schools, the mosque and dispensary. Arable land sits on flats between, once the floor of the landslide lake. It was 500 meters deep at Gol and at least 90 kilometers long. Farms and fields are also scattered over river terraces recording the sequence of incision by the river.

2010-09HewittF10.jpgClick to Enlarge ImageOf course, the hands of local farmers and their wives have made the terraced fields, fertile soil and channels to carry irrigation water. Stone from the landslide is used for terracing and other construction, broken from boulders left conveniently on the valley floor. The villagers at Gol have their stories too, telling of a former lake and boats tied up at places far above today’s river; of the cataclysm that created the lake; and of a flood from up-valley that destroyed it. I suspect this also reflects an eye for landscape more than remembered history. At least, our age determinations put the landslide at 4,300 years ago (+/-170 years)—long before permanent settlement!

Many villages like Gol occupy landforms developed through landslide interruptions. Skardu and Khapalu, the main towns of Baltistan, are spread over rock avalanche areas. At Skardu and Gilgit the airports lie on terrace levels related to former landslide dams. Taxiing from the runway at Skardu you pass bluffs in fine-grained yellow sediments laid down in a vast lake dammed by the landslide at Katzarah. One can only marvel at the extraordinary range of resources and uses people have found for the landslides.








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