Magnitude6.3

Reviewed by USGSNew Zealand108y ago

M6.3 earthquake 84 km SSE of Castlepoint, New Zealand

Friday, September 12, 1919, 06:06:04 UTC · 41.589°S, 176.635°E

A magnitude 6.3 earthquake struck 84 km SSE of Castlepoint, New Zealand on Friday, September 12, 1919, 06:06:04 UTC, at a depth of 15.0 km (shallow). It is the strongest earthquake within 300 km since an M6.8 on August 5, 1917.

Magnitude
6.3
Strong · mw
Depth
15 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 earthquake

In context

How big was it, and why here?

Energy released

44 kilotons of TNT

That is about 3 times the Hiroshima bomb. It released about 92 times the energy of a magnitude 5.0.

Tectonic setting

19 km

from the nearest mapped plate boundary, between the Kermadec and Pacific 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 100 km

USGS has not published any M2.5+ earthquake within 100 km in the 30 days after this event.

Regional history

Past M5+ earthquakes within 300 km

USGS lists 3 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 7 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 3 recorded deaths. The most severe:

  1. 1848M6.0

    Awatere River, Marlborough

    18 Oct 1848 · 219 km away

    3 deathstsunami

  2. 1855M8.0

    Wellington,Waiouru,Wanganui,Otaki

    23 Jan 1855 · 141 km away

    Severe damage ($5–24M)tsunami

  3. 1848M7.9

    N.

    15 Oct 1848 · 181 km away

    Limited damage (under $1M)tsunami

  4. 1843M7.5

    Wanganui

    8 Jul 1843 · 233 km away

    tsunami

  5. 1904M7.5

    E Of North Island

    8 Aug 1904 · 125 km away

    tsunami

  6. 1855M5.5

    New Zealand

    11 Feb 1855 · 278 km away

    tsunami

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

Nearby trackers

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