In the small hours of February 18, 1911, the Central Pamirs - in what is now the Gorno-Badakhshan Autonomous Area of the Republic of Tajikistan - was hit by a violent earthquake which touched off a giant landslide in the Murgab river valley. It came to be known as the "Usoi Obstruction" in memory of kishlak (hamlet) Usoi wiped out with all its residents. That obstruction dammed the river valley where a large lake was formed. A small village, Sarez, found itself under its water, hence the name - Lake Sarez. As much as 17 cubic kilometers of water have accumulated there, 3,250 meters above sea level, in these nine decades. Every year the level of the lake's water rises by another 0.2m. Should the water burst the natural dam formed by the obstruction, it will cause terrible havoc in a large territory of Central Asia with a population of six million. That tragedy can break out anytime.
by Leonid PAPYRIN, head of the GEON geophysical and geoecological research division, Ministry for Natural Resources of the Russian Federation
A MONSTER BIDING ITS TIME
Back in 1967 research teams of the TAJIKGEOLOGIA R&D Association and the National Institute of Engineering Geology and Hydrogeology (VSEGINGEO) were carrying out aerial surveys to assess the hazard of mud and rock torrents coming down from the high-mountain lakes of the Pamirs. Surveying the right slope of the Lake Sarez basin, just between the Usoi Obstruction (rock dam) and the sai (gorge) Biromband (4,000 to 4,300 meters above sea level), they discovered crevices (fissures) extending for something like two kilometers - what came to be known as the Right-Shore Landslip. Should it slide into Lake Sarez, its water would destroy the lower northern part of the rock dam and set off an immense torrent of mud and rock rushing down the valleys of the rivers Bartang, Pyanzh and Amu Darya.
The possible disaster may be very much like one that occurred in 1963 on northern Italy's river Piave where a giant landslide ... Читать далее