K2 lies in the northwestern Karakoram Range. The Tarim sedimentary basin borders the range on the north and the Lesser Himalayas on the south. Melt waters from vast glaciers, such as those south and east of K2, feed agriculture in the valleys and contribute significantly to the regional fresh-water supply. The Karakoram Range lies along the southern edge of the Eurasian tectonic plate and is made up of ancient sedimentary rocks (more than 390 million years old). Those strata were folded and thrust-faulted, and granite masses were intruded, when the Indian plate collided with Eurasia, beginning more than 100 million years ago.
K2 is only ranked 22nd by topographic prominence, a measure of a mountain's independent stature, because it is part of the same extended area of uplift (including the Karakoram, the Tibetan Plateau, and the Himalaya) as Mount Everest, in that it is possible to follow a path from K2 to Everest that goes no lower than 4,594 metres (15,072 ft), at Mustang Lo. Many other peaks which are far lower than K2 are more independent in this sense.
However, K2 is notable for its local relief as well as its total height. It stands over 3,000 metres (9,800 ft) above much of the glacial valley bottoms at its base. More extraordinary is the fact that it is a consistently steep pyramid, dropping quickly in almost all directions. The north side is the steepest: there it rises over 3,200 metres (10,500 ft) above the K2 (Qogir) Glacier in only 3,000 metres (9,800 ft) of horizontal distance. In most directions, it achieves over 2,800 metres (9,200 ft) of vertical relief in less than 4,000 metres (13,000 ft).
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