QuakeIndex

Earthquake · reviewed by a seismologist

M 3.2mb_lg

Earthquake near Floresville, TX

Yes: an earthquake was likely felt in Floresville in the last 24 hours. M 3.1, 82 km (51 mi) WSW of Floresville, at 3:20 am CST on 12 November 2026 (09:20 UTC); the estimated shaking in Floresville was intensity II (weak). 1 person has reported feeling it to USGS. Every earthquake near Floresville

This page: a magnitude 3.2 earthquake was recorded 27 km (17 mi) east-southeast of Floresville, TX, at 11:32 pm CST on 21 December 2018 (05:32 UTC), 5.0 km deep. 9 people have reported feeling it to USGS.

USGS: 14 km NE of Falls City, Texas

76 km (47 mi) SE of San Antonio, TX

11:32 pm CST, Dec 21, 2018 · · 5.0 km deep · released about 1,900 lb of TNT

10 km30 km60 km120 km N Karnes County 17 kmWilson County 23 kmDeWitt County 52 kmGuadalupe County 59 kmGonzales County 60 kmGoliad County 63 kmAtascosa County 65 kmBee County 73 kmBexar County 75 km
Distance rings around the epicentre, with the nearest towns at their true direction and later quakes as coloured dots. Not a shaking map — see the USGS ShakeMap for that.
When
11:32 pm CST on 21 December 2018 ()
Where
27 km (17 mi) east-southeast of Floresville, TX · earthquakes near Floresville
Texas today
every earthquake in Texas in the last 24 hours
Magnitude
M 3.2 (mb_lg)
Depth
5.0 km below the surface
Felt
9 reports · strongest reported intensity III
Nearest
Karnes County, 17 km SSE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 498 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

At this magnitude and depth, people at rest would likely notice it out to about 190 km (118 mi) from the epicentre. In Floresville, 27 km away, the estimate is intensity III (weak). Estimated from magnitude, depth and distance with the intensity equation USGS Did You Feel It? uses; felt reports, where there are any, are the measurement.

Likely felt in: Karnes City 19 km, intensity III · Stockdale 21 km, intensity III · Nixon 27 km, intensity III · Floresville 27 km, intensity III · Yorktown 39 km, intensity III. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 1,900 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.2 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 180,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 7,900× the energy of this one
  3. Magna, Utah 2020 M 5.7 5,600× the energy of this one
  4. This earthquake M 3.2 about 1,900 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 2× 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

The largest earthquake within 50 km since 2016 was M 4.0 on 2018-05-01 — about 16 times the energy of this one.

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 29.0573, -97.8935. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Karnes County, TX 17 km (11 mi) SSE earthquakes near Karnes County
Wilson County, TX 23 km (14 mi) NW earthquakes near Wilson County
DeWitt County, TX 52 km (32 mi) E earthquakes near DeWitt County
Guadalupe County, TX 59 km (36 mi) N earthquakes near Guadalupe County
Gonzales County, TX 60 km (37 mi) NE earthquakes near Gonzales County
Goliad County, TX 63 km (39 mi) SE earthquakes near Goliad County

Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.

Aftershocks so far

57 earthquakes have been recorded within 50 km since this one.

  1. 1.5 16 km SSE of Nixon, Texas
  2. 1.9 17 km SSE of Nixon, Texas
  3. 1.5 10 km ESE of Smiley, Texas
  4. 1.6 9 km ESE of Smiley, Texas
  5. 1.5 3 km ESE of Falls City, Texas
  6. 2.7 16 km ENE of Falls City, Texas
  7. 1.9 4 km ESE of Falls City, Texas
  8. 1.7 1 km NNW of Falls City, Texas
  9. 1.8 4 km SE of Falls City, Texas
  10. 1.9 2 km E of Falls City, Texas
  11. 1.8 4 km SE of Falls City, Texas
  12. 1.9 3 km ESE of Falls City, Texas
  13. 1.8 3 km SE of Falls City, Texas
  14. 2.4 2 km E of Falls City, Texas
  15. 2.0 2 km ESE of Falls City, Texas

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

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.