Reviewed by USGSZimbabwe10y ago
M5.6 earthquake 171 km SSE of Chipinge, Zimbabwe
Thursday, September 22, 2016, 20:06:11 UTC · 21.552°S, 33.411°E
A magnitude 5.6 earthquake struck 171 km SSE of Chipinge, Zimbabwe on Thursday, September 22, 2016, 20:06:11 UTC, at a depth of 10.0 km (shallow). USGS received 3 “Did You Feel It?” reports, with a maximum reported intensity of III (weak). The USGS PAGER alert is green: low likelihood of casualties and damage. It is the strongest earthquake within 300 km since an M5.6 on March 15, 2006.
- Magnitude
- 5.6
- Moderate · mww
- Depth
- 10 km
- Shallow
- Felt reports
- 3
- Max intensity III
- Est. shaking
- VII
- Very strong (ShakeMap)
- PAGER alert
- Green
- Impact estimate
- Tsunami
- No flag
- USGS feed
Outlined circle: this earthquakeDashed circle: 75 km aftershock search areaColoured lines: estimated shaking intensity (USGS ShakeMap)
In context
How big was it, and why here?
Energy released
4 kilotons of TNT
That is about 1/4 of the Hiroshima bomb. It released about 8 times the energy of a magnitude 5.0.
Tectonic setting
39 km
from the nearest mapped plate boundary, between the Somali and African plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
10 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
Reports sent by people to USGS, grouped by place (most reports first). Intensity uses the Modified Mercalli scale (I–X): what people felt, not the magnitude.
| Place | Intensity | Reports | Distance |
|---|---|---|---|
| Harare, Harare, Zimbabwe | III · Weak | 1 | 473 km |
| Chimoio, Manica, Mozambique | III · Weak | 1 | 265 km |
| Beira, Sofala, Mozambique | III · Weak | 1 | 243 km |
USGS PAGER estimate
Who was exposed to shaking
USGS publishes PAGER impact estimates for significant earthquakes, usually within an hour. No populated area was estimated to feel noticeable shaking.
After the main event
Aftershocks within 75 km
USGS lists 1 M2.5+ earthquake within 75 km in the following 30 days; the largest was M4.3 on September 25, 2016. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 20 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.0160 km SE of Chipinge, ZimbabweFebruary 22, 2006 · 31 km NE of this epicenter
- 6.1203 km N of Chokwé, MozambiqueMay 19, 1940 · 144 km SW of this epicenter
- 6.195 km ESE of Chimanimani, ZimbabweMay 10, 1951 · 153 km N of this epicenter
- 6.0209 km SSE of Chipinge, ZimbabweMarch 19, 1951 · 39 km SE of this epicenter
- 5.8184 km SSE of Chipinge, ZimbabweJuly 20, 1957 · 16 km S of this epicenter
- 5.7161 km SE of Chipinge, ZimbabweFebruary 23, 2006 · 23 km NE of this epicenter
- 5.6146 km SE of Chipinge, ZimbabweMarch 15, 2006 · 48 km N of this epicenter
- 5.4134 km SSE of Chipinge, ZimbabweFebruary 22, 2006 · 39 km N of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 1 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 4 recorded deaths. The most severe:
- 2006M7.0
Mozambique
22 Feb 2006 · 31 km away · intensity V
4 deathsModerate damage ($1–5M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.