M6.5 earthquake 132 km WSW of Moijabana, Botswana

Monday, April 3, 2017, 17:40:18 UTC · 22.678°S, 25.156°E

A magnitude 6.5 earthquake struck 132 km WSW of Moijabana, Botswana on Monday, April 3, 2017, 17:40:18 UTC, at a depth of 29.0 km (shallow). USGS received 937 “Did You Feel It?” reports, with a maximum reported intensity of VII (very strong). The USGS PAGER alert is green: low likelihood of casualties and damage. No earthquake of this size or larger appears within 300 km in the USGS catalog since 1900.

Magnitude: 6.5; Strong · mww
Depth: 29 km; Shallow
Felt reports: 937; Max intensity VII
Est. shaking: VIII; Severe (ShakeMap)
PAGER alert: Green; Impact estimate
Tsunami: No flag; USGS feed

Outlined circle: this earthquakeDashed circle: 100 km aftershock search areaColoured lines: estimated shaking intensity (USGS ShakeMap)

In context

How big was it, and why here?

Energy released

85 kilotons of TNT

That is about 6 times the Hiroshima bomb. It released about 178 times the energy of a magnitude 5.0.

Tectonic setting

306 km

from the nearest mapped plate boundary, between the Somali and African plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.

Depth: shallow

29 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
Johannesburg, Gauteng, South Africa	III · Weak	133	487 km
Pretoria, Gauteng, South Africa	III · Weak	100	460 km
Gaborone, Gaborone, Botswana	IV · Light	90	233 km
Verwoerdburg, Gauteng, South Africa	III · Weak	78	467 km
Midrand, Gauteng, South Africa	III · Weak	42	476 km
Maputo, Maputo, Mozambique	III · Weak	36	835 km
Harare, Harare, Zimbabwe	III · Weak	24	818 km
Krugersdorp, Gauteng, South Africa	III · Weak	22	462 km
Benoni, Gauteng, South Africa	III · Weak	21	502 km
Francistown, Francistown, Botswana	IV · Light	15	295 km
Ellisras, Limpopo, South Africa	IV · Light	15	288 km
Bulawayo, Bulawayo, Zimbabwe	III · Weak	15	451 km

I felt it — report to USGS ↗

USGS PAGER estimate

Who was exposed to shaking

Modelled from the ShakeMap and population data. Alert level green: low likelihood of casualties and damage.

VII · Very strong shaking: 1,700 people
VI · Strong shaking: 60,000 people
V · Moderate shaking: 2.5 million people
IV · Light shaking: 16 million people
III · Weak shaking: 7.6 million people

Estimated shaking in nearby towns

MoijabanaPopulation 2,800VI · Strong
KhudumelapyePopulation 2,000VI · Strong
MopipiPopulation 3,300VI · Strong
DutlwePopulation 1,100V · Moderate
LetlhakanePopulation 18,000V · Moderate
RakopsPopulation 5,200V · Moderate
GaboronecapitalPopulation 208,000IV · Light
GwerucapitalPopulation 146,000IV · Light

After the main event

Aftershocks within 100 km

USGS lists 7 M2.5+ earthquakes within 100 km in the following 30 days; the largest was M5.0 on April 5, 2017. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.

Time after the mainshock on a logarithmic scale (first hours stretched), magnitude on the vertical axis. M2.5+ events from USGS.

Regional history

Past M5+ earthquakes within 300 km

USGS lists no earlier M5.0+ earthquakes within 300 km.

Nearby trackers