diga di Usoi
Italy
The Usoi Dam is a natural landslide dam along the Murghab River in Tajikistan. At 567 metres (1,860 ft) high, it is the tallest dam in the world, either natural or man-made. The dam was created on 18 February 1911, when the 7.4-Ms Sarez earthquake caused a massive landslide that blocked the flow of
the river. The dam is formed of approximately 2 cubic kilometres (0.48 mi3) of rock dislodged from the steeply sloped river valley of the Murghab, which cuts from east to west through the high and rough Pamir Mountains. It is named after the village of Usoi, which was completely buried by the 1911 landslide. The dam rises to a height of 500 to 700 metres (1,600 to 2,300 ft) from the original valley floor. The basin formed by Usoi Dam now holds Sarez Lake, a 55.8-kilometre (34.7 mi)-long lake holding 16.074 cubic kilometres (13,031,000 acre⋅ft) of water. Water does not flow over the top of the dam, which would quickly cause it to erode away; instead, water seeps out of the base of the dam at a rate which approximately matches the rate of inflow, maintaining the lake at a relatively constant level. The level thus only rises an average of 20 cm per year. The flow averages about 45 cubic meters...
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