At least 780 people killed and many buildings collapsed in the Nyingchi-Qamdo-Zhamo (Rima, Zayu) area of eastern Tibet. Sandblows, ground cracks and large landslides occurred in the area.
In the Medog area, the village of Yedong slid into the Yarlung Zangbo (Brahmaputra) River and was washed away. The quake was felt at Lhasa and in Sichuan and Yunnan Provinces, China. Severe damage (X) also occurred in the Sibsagar-Sadiya area of Assam, India and in the surrounding hills. About 70 villages were destroyed in the Abor Hills, mostly by landslides.
Large landslides blocked the Subansiri River. This natural dam broke 8 days later, creating a wave 7 m (23 ft) high which innundated several villages and killed 536 people. The quake was felt (VI) as far away as Calcutta. Seiches were observed in many lakes and fjords of Norway and in at least 3 reservoirs in England. Many sources call this the Assam-Tibet earthquake or even the Assam earthquake, even though nearly all place the epicenter in Tibet.
Thus it is possible that the casualties for Tibet are not included in the total, as well as those from the Subansiri River flood. Furthermore, Gu et al. do not give casualty totals for Yedong or other areas of the most severe damage in Tibet. Therefore, the actual casualty toll may be much higher than the value given.
N.B: The magnitude for this earthquake has been recalculated since the following articles were written. Magnitude 8.6 is a better determination of the size of this earthquake.
Intensity scale X at Sadya, Passighat, Dum Duma, Dibrugarh, North Lakhimpur, and Sibsagar; IX at Digboi and Galaghat; VIII at Tezpur, Ganhati, and Shillong; VI at Daca, Calcutta Dhubri, Darjeeling, and Imphal. Macroseismic area 1,794,000 sq km, of which 49,700 sq km suffered great damage.
This great earthquake, destructive in Assam and Tibet, has a calculated magnitude of 8.6 and Strasbourg regards it as the most important since the introduction of seismological observing stations. Alterations of relief were brought about by many rock falls in the Mishmi Hills and destruction of forest areas. In the Arbor Hills 70 villages were destroyed with 156 casualties due to landslides. Dykes blocked the tributaries of the Brahmaputra; that in the Dibang valley broke without causing damage, but that at Subansiri opened after an intermal of 8 days and the wave, 7 metres high, submerged several villages and killed 532 persons.
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