Magnitude4.9

Reviewed by USGSIndia35y ago

M4.9 earthquake 24 km ENE of Uttarkāshi, India

Sunday, October 20, 1991, 05:32:26 UTC · 30.790°N, 78.686°E

A magnitude 4.9 earthquake struck 24 km ENE of Uttarkāshi, India on Sunday, October 20, 1991, 05:32:26 UTC, at a depth of 26.5 km (shallow). It is the strongest earthquake within 300 km since an M6.8 on October 19, 1991.

Magnitude
4.9
Light · mb
Depth
27 km
Shallow
Felt reports
0
Did You Feel It?
Est. shaking
—
No ShakeMap
PAGER alert
None
Not issued
Tsunami
No flag
USGS feed

Outlined circle: this earthquakeDashed circle: 50 km aftershock search area

In context

How big was it, and why here?

Energy released

338 tons of TNT

That is about 1/45 of the Hiroshima bomb. A magnitude 5.0 releases about 1 times more energy.

Tectonic setting

85 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

27 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 50 km

USGS lists 3 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M4.2 on October 27, 1991. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.

M3M4M51h6h1d3d7d14d30dMainshock M4.9
Time after the mainshock on a logarithmic scale (first hours stretched), magnitude on the vertical axis. M2.5+ events from USGS.
  1. 4.2Uttaranchal, India35y ago · 42 km S of this epicenter
  2. 4.034 km E of Uttarkāshi, India35y ago · 11 km E of this epicenter
  3. 4.234 km ENE of Uttarkāshi, India35y ago · 11 km NE of this epicenter

Regional history

Past M5+ earthquakes within 300 km

USGS lists 82 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:

History · NOAA

Deadliest earthquakes in this area

NOAA’s significant-earthquake database lists 11 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 21,348 recorded deaths. The most severe:

  1. 1905M7.9

    Kangra

    4 Apr 1905 · 262 km away · intensity X

    19,000 deaths$25 million damagetsunami

  2. 1991M7.0

    Chamoli, Uttarkashi, New Delhi, Chandigarh

    19 Oct 1991 · 8 km away · intensity VIII

    2,000 deaths$60 million damage

  3. 1980M6.5

    Pithoragarh

    29 Jul 1980 · 267 km away

    200 deaths$245 million damage

  4. 1966M6.3

    Nepal-India

    27 Jun 1966 · 250 km away · intensity VIII

    80 deaths$1 million damage

  5. 1975M6.8

    Kashmir: Kinnaur District

    19 Jan 1975 · 187 km away

    47 deathsModerate damage ($1–5M)

  6. 1966M5.6

    N

    15 Aug 1966 · 233 km away

    15 deathsLimited damage (under $1M)

NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.

Nearby trackers

Closest city pages