QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8ml

Earthquake near Karnes City, TX

Yes: an earthquake was likely felt in Karnes City in the last 24 hours. M 3.1, 101 km (63 mi) W of Karnes City, at 3:20 am CST on 12 November 2026 (09:20 UTC); the estimated shaking in Karnes City was intensity II (weak). Every earthquake near Karnes City

This page: a magnitude 1.8 earthquake was recorded 16 km (10 mi) north of Karnes City, TX, at 2:22 pm CST on 21 December 2018 (20:22 UTC), 8.0 km deep.

USGS: 11 km ENE of Falls City, Texas

76 km (48 mi) SE of San Antonio, TX

2:22 pm CST, Dec 21, 2018 · · 8.0 km deep · released about 15 lb of TNT

10 km30 km60 km120 km N Karnes County 14 kmWilson County 23 kmDeWitt County 54 kmGuadalupe County 62 kmAtascosa County 62 kmGoliad County 62 kmGonzales County 63 kmBee County 70 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
2:22 pm CST on 21 December 2018 ()
Where
16 km (10 mi) north of Karnes City, TX · earthquakes near Karnes City
Texas today
every earthquake in Texas in the last 24 hours
Magnitude
M 1.8 (ml)
Depth
8.0 km below the surface
Felt
no reports yet
Nearest
Karnes County, 14 km SSE
Status
Reviewed by a seismologist

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

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth, people at rest would likely notice it out to about 15 km (9 mi) from the epicentre. In Karnes City, 16 km away, the estimate is intensity II (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.

Earthquakes near other towns within 30 km: Poth, Stockdale, Kenedy, Runge, Floresville.

How big was it?

This earthquake released about 15 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,000,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 710,000× the energy of this one
  3. Around the size people start to feel M 3.0 63× the energy of this one
  4. This earthquake M 1.8 about 15 lb of TNT

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 2,000 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 29.0270, -97.9150. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Karnes County, TX 14 km (9 mi) SSE earthquakes near Karnes County
Wilson County, TX 23 km (15 mi) NW earthquakes near Wilson County
DeWitt County, TX 54 km (34 mi) E earthquakes near DeWitt County
Guadalupe County, TX 62 km (38 mi) N earthquakes near Guadalupe County
Atascosa County, TX 62 km (39 mi) WSW earthquakes near Atascosa County
Goliad County, TX 62 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

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

  1. 2.4 2 km E of Falls City, Texas
  2. 2.0 2 km ESE of Falls City, Texas
  3. 2.2 3 km E of Falls City, Texas
  4. 2.7 2 km E of Falls City, Texas
  5. 2.4 8 km NNE of Falls City, Texas
  6. 1.5 9 km ESE of Smiley, Texas
  7. 1.8 8 km ESE of Smiley, Texas
  8. 1.6 11 km E of Smiley, Texas
  9. 2.2 8 km ESE of Smiley, Texas
  10. 1.8 8 km ESE of Smiley, Texas
  11. 1.7 8 km ESE of Smiley, Texas
  12. 1.7 8 km ESE of Smiley, Texas
  13. 3.0 13 km ESE of Smiley, Texas
  14. 2.5 23 km WNW of Pawnee, Texas
  15. 2.5 12 km S of Smiley, 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.