Earthquake · reviewed by a seismologist
M 3.1ml
Earthquake near Tanque Verde, AZ
USGS: 21 km E of Tanque Verde, Arizona
35 km (22 mi) ENE of Tucson, AZ
- When
- 3:50 am MST on 28 September 2023 ()
- Where
- 22 km (13 mi) E of Tanque Verde, AZ · earthquakes near Tanque Verde
- Magnitude
- M 3.1 (ml)
- Depth
- 12 km below the surface
- Felt
- 25 reports · strongest reported intensity III
- Nearest
- Cochise County, 81 km ESE
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 986 days ago
A magnitude 3.1 earthquake was recorded 22 km (13 mi) E of Tanque Verde, AZ, at 3:50 am MST on 28 September 2023 (10:50 UTC). 25 people have reported feeling it to USGS. This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.
Earthquakes near other towns within 30 km: Mescal, Vail.
How big was it?
This earthquake released about 1,300 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.1 would have released about 32 times as much.
- Northridge, California 1994 M 6.7 250,000× the energy of this one
- Mineral, Virginia 2011 M 5.8 11,000× the energy of this one
- Magna, Utah 2020 M 5.7 7,900× the energy of this one
- This earthquake M 3.1 about 1,300 lb of TNT
- Around the size people start to feel M 3.0 this one released 1.4× more
Energy from the Gutenberg–Richter relation (log10E = 1.5M + 4.8), rounded to two figures; bar length is magnitude, which is already a logarithm of energy. Magnitudes of past earthquakes from the USGS catalogue.
For this area
No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.
Before 2016, the USGS record since 1900 lists no earthquake of M5 or more within 50 km.
Since 2016: the QuakeIndex catalogue (US, M1.5+), built from the USGS FDSN event service. Before 2016: USGS ComCat, M5+ from 1900. Distances are between epicentres. This is the record, not a forecast.
Where
Epicentre 32.2208, -110.5104. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Cochise County, AZ | 81 km (50 mi) | ESE | earthquakes near Cochise County |
| Santa Cruz County, AZ | 84 km (52 mi) | SSW | earthquakes near Santa Cruz County |
| Graham County, AZ | 99 km (61 mi) | NE | earthquakes near Graham County |
| Pinal County, AZ | 112 km (69 mi) | NW | earthquakes near Pinal County |
| Pima County, AZ | 120 km (75 mi) | W | earthquakes near Pima County |
| Greenlee County, AZ | 164 km (102 mi) | NE | earthquakes near Greenlee County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
1 earthquake has been recorded within 50 km since this one.
Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of . QuakeIndex does not forecast aftershocks. When USGS issues an operational aftershock forecast it appears on the USGS event page.
On USGS
- The official USGS event page — the source of record for every value above
- Did you feel it? Report it to USGS — reports go to USGS, not to us
- ShakeMap for this event, when USGS has produced one
QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.