QuakeIndex

Earthquake · reviewed by a seismologist

M 3.6ml

Earthquake near Salida, CO

No earthquake was likely felt in Salida in the 24 hours to 7:09 am MST (14:09 UTC). The last one was M 3.4, 184 km (114 mi) SSE, at 3:34 am MST on 8 November 2026, estimated intensity II (weak) in town; 2 felt reports to USGS. Every earthquake near Salida

This page: a magnitude 3.6 earthquake was recorded 24 km (15 mi) southeast of Salida, CO, at 3:17 pm MST on 30 November 2017 (22:17 UTC), 5.0 km deep. 61 people have reported feeling it to USGS.

USGS: 4 km NNW of Coaldale, Colorado

3:17 pm MST, Nov 30, 2017 · · 5.0 km deep · released about 3.8 tons of TNT

10 km30 km60 km120 km N Fremont County 31 kmCuster County 49 kmSaguache County 57 kmChaffee County 58 kmTeller County 73 kmPark County 80 kmAlamosa County 93 kmLake County 102 kmHuerfano County 107 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
3:17 pm MST on 30 November 2017 ()
Where
24 km (15 mi) southeast of Salida, CO · earthquakes near Salida
Magnitude
M 3.6 (ml)
Depth
5.0 km below the surface
Felt
61 reports · strongest reported intensity V
Measured shaking
intensity III (ShakeMap)
Nearest
Fremont County, 31 km E
Nearest mapped fault
Northern Sangre de Cristo fault, 15 km from its surface trace — near is not the same as on
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2984 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 69 km (43 mi) from the epicentre. In Salida, 24 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.

How big was it?

This earthquake released about 3.8 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.6 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 45,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 2,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 1,400× the energy of this one
  4. This earthquake M 3.6 about 3.8 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 7.9× 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 38.4051, -105.7807. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Fremont County, CO 31 km (20 mi) E earthquakes near Fremont County
Custer County, CO 49 km (30 mi) SE earthquakes near Custer County
Saguache County, CO 57 km (36 mi) SW earthquakes near Saguache County
Chaffee County, CO 58 km (36 mi) NW earthquakes near Chaffee County
Teller County, CO 73 km (45 mi) NE earthquakes near Teller County
Park County, CO 80 km (49 mi) N earthquakes near Park County

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

Aftershocks so far

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

  1. 2.4 17 km NE of Saguache, Colorado
  2. 1.5 9 km SSW of Garfield, Colorado
  3. 2.5 19 km WNW of Cañon City, Colorado
  4. 1.5 2 km SE of Maysville, Colorado
  5. 1.5 9 km N of Cotopaxi, Colorado
  6. 1.5 2 km SSE of Cotopaxi, Colorado
  7. 2.3 3 km SW of Cotopaxi, Colorado
  8. 1.5 2 km S of Coaldale, Colorado
  9. 1.9 16 km S of Cotopaxi, Colorado

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.