Preliminary77y ago
M8.6 earthquake 1950 Assam-Tibet Earthquake
Tuesday, August 15, 1950, 14:09:34 UTC · 28.363°N, 96.445°E
A magnitude 8.6 earthquake struck 1950 Assam-Tibet Earthquake on Tuesday, August 15, 1950, 14:09:34 UTC, at a depth of 15.0 km (shallow). No earthquake of this size or larger appears within 300 km in the USGS catalog since 1900.
- Magnitude
- 8.6
- Great · mw
- Depth
- 15 km
- Shallow
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- VIII
- Severe (ShakeMap)
- PAGER alert
- None
- Not issued
- Tsunami
- No flag
- USGS feed
Outlined circle: this earthquakeDashed circle: 400 km aftershock search areaColoured lines: estimated shaking intensity (USGS ShakeMap)
In context
How big was it, and why here?
Energy released
120 megatons of TNT
That is about 7,955 times the Hiroshima bomb. It released about 251,189 times the energy of a magnitude 5.0.
Tectonic setting
27 km
from the nearest mapped plate boundary, between the Eurasian and Indian plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
15 km
Shallow earthquakes (under 70 km) produce the strongest surface shaking for their size, so they are the ones most likely to cause damage near the epicenter.
Did You Feel It?
Where it was felt
No “Did You Feel It?” reports have been published for this event yet. If you felt it, you can add your report on the USGS website.
I felt it — report to USGS ↗USGS PAGER estimate
Who was exposed to shaking
USGS publishes PAGER impact estimates for significant earthquakes, usually within an hour. No PAGER estimate is available for this event.
After the main event
Aftershocks within 400 km
USGS lists 33 M2.5+ earthquakes within 400 km in the following 30 days; the largest was M6.3 on August 18, 1950. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
- 6.2India77y ago · 154 km SW of this epicenter
- 5.823 km WNW of Shi Yomi, India77y ago · 225 km W of this epicenter
- 5.7163 km SSW of Qamdo, China77y ago · 152 km N of this epicenter
- 5.9157 km SSW of Qamdo, China77y ago · 158 km N of this epicenter
- 5.5143 km NE of Shi Yomi, India77y ago · 180 km NW of this epicenter
- 5.7156 km NE of Shi Yomi, India77y ago · 185 km NW of this epicenter
- 5.760 km N of Pāsighāt, India77y ago · 112 km W of this epicenter
- 5.5eastern Xizang-India border region77y ago · 202 km NW of this epicenter
Regional history
Past M5+ earthquakes within 300 km
USGS lists 19 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.637 km S of Sarupathar, IndiaJanuary 27, 1931 · 279 km S of this epicenter
- 7.373 km W of Shi Yomi, IndiaJuly 29, 1947 · 276 km W of this epicenter
- 7.264 km NNE of Sarupathar, IndiaDecember 12, 1908 · 194 km S of this epicenter
- 6.528 km SSW of Sarupathar, IndiaAugust 31, 1937 · 269 km S of this epicenter
- 6.481 km NNE of Sarupathar, IndiaAugust 31, 1906 · 188 km SE of this epicenter
- 6.3167 km NNE of Shi Yomi, IndiaNovember 21, 1938 · 212 km NW of this epicenter
- 5.95 km NE of Tuensang, IndiaNovember 28, 1948 · 277 km SW of this epicenter
- 5.86 km NNW of Sarupathar, IndiaJune 19, 1936 · 236 km S of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 4 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 1,530 recorded deaths. The most severe:
- 1950M8.6
India-China
15 Aug 1950 · 16 km away · intensity XI
1,530 deaths$20 million damagetsunami
- 1932M7.0
Assam
14 Aug 1932 · 279 km away
Moderate damage ($1–5M)
- 1947M7.9
India-China
29 Jul 1947 · 240 km away
- 1908M7.2
Kachin
12 Dec 1908 · 196 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.