At 3.40 am on the 2nd of August 2011 (7.40 pm on the 1st, GMT) a magnitude 5.1 earthquake occurred in Western Tibet (Xizang Province, China) at a depth of about 13 km. This is likely to have caused considerable disturbance at ground level, though there are no reports of any casualties or notable damage.
Map showing the quake location (green arrow) and the nearest settlement (A).
Tibet is extremely sparsely populated, with only 2.2/km², comparable to Australia at 2.8/km²; so quite a lot can happen without affecting anyone.
The Tibetan Plateau is a vast upland created by the impact of India and Eurasia; the 32 highest mountains in the world are on the Plateau (the 33rd, Tirich Mir, is in the nearby Hindu Kush, Afghanistan). India is still moving northwards, but Eurasia is unable to do the same, resulting in an unusual degree of folding and uplift. This has resulted in a number of faults running east-west across the plateau, with sections being forced eastward into China.
Faults and Plate Movement on the Tibetan Plateau.