M2.1 earthquake 4 km SW of Grand Tower, Illinois
A magnitude 2.1 earthquake struck 4 km SW of Grand Tower, Illinois on Mon, Jul 30, 2012, 11:48 PM CDT (04:48 UTC), 11 km (7 mi) below the surface.
Map
Where this earthquake was located, with the others nearby. Select one for its page.
The earthquake
- Magnitude
- 2.1 (Md, duration), micro
- Magnitude from
- NM
- Local time
- UTC
- 2012-07-31 04:48:35 UTC
- Depth
- 10.5 km (6.5 mi), shallow
- Epicenter
- 37.601° N, 89.534° W
- Region
- Illinois
- Felt reports
- 6
- Tsunami flag
- No
- Status
- Reviewed by a seismologist
Magnitude estimates
Different scales measure different things and differ by a few tenths. The USGS marks one as preferred, and it is the one this page uses.
| Mag. | Scale | Computed by | Notes |
|---|---|---|---|
| 2.1 | Md, duration | NM | Preferred · Reviewed · ±0.043 · 2 stations |
| 2.1 | Md, duration | USGS National Earthquake Information Center | Reviewed |
What happened
The USGS’s account of the effects of this earthquake.
Felt at Cape Girardeau and Sikeston.
From the USGS event page for nm609493. U.S. Geological Survey text and figures are in the public domain.
Did you feel it?
6 people reported to the USGS what they felt; the strongest reported shaking was III, weak shaking.
How well it is located
Reviewed by a seismologist.
- Location uncertainty
- About 0.8 km horizontally, 1.6 km in depth
- Magnitude uncertainty
- ±0.04
- Depth from
- From location
- Station coverage gap
- 61°
- Stations used
- 17
Nearest places
Distance and direction from each place to the epicenter, with its forecast.
Nearby
Within 100 km, magnitude 1.5 and up: 3 in the 60 days after this one and 1 in the 30 days before it.
After
- 1.87 km SSE of Matthews, Missouri · 5166 days ago · 8 km deep · 100 km away
- 2.04 km SSE of Jackson, Missouri · 5130 days ago · 14 km deep · 30 km away
- 1.911 km NNE of Bonne Terre, Missouri · 5121 days ago · 14 km deep · 99 km away
Before
Earthquakes todayIllinois earthquakesLive radar here
Sources
From the USGS Earthquake Hazards Program and its partner networks, event nm609493 (also filed as nm073112b, usp000jpp3). Read Fri, Oct 2, 2026, 5:10 PM UTC.