May 31, 1935 to May 31, 1935
Quetta, PakistanThe 1935 Quetta earthquake occurred on 31 May between 2:33 am and 3:40 am at Quetta, Balochistan, British India (now part of Pakistan). The earthquake had a magnitude of 7.7 Mw and anywhere between 30,000 and 60,000 people died from the impact. This ranked as the deadliest earthquake that hit South Asia until the 2005 Kashmir earthquake. The quake was centred 4 km south-west of Ali Jaan, Balochistan, British India.
Quetta and its neighboring towns lie in the most active seismic region of Pakistan atop the Chaman and Chiltan faults. Movement on the Chaman Fault resulted in an earthquake early in the morning on 31 May 1935 estimated anywhere between the hours of 2:33 am and 3:40 am which lasted for three minutes with continuous aftershocks. Although there were no instruments good enough to precisely measure the magnitude of the earthquake, modern estimates cite the magnitude as being a minimum of 7.7 Mw and previous estimates of 8.1 Mw are now regarded as an overestimate. The epicenter of the quake was established to be 4-kilometres south-west of the town of Ali Jaan in Balochistan, some 153-kilometres away from Quetta in British India. The earthquake caused destruction in almost all the towns close to Quetta, including the city itself, and tremors were felt as far as Agra, now in India.