Earthquakes on October 23, 2021
303
EARTHQUAKES on October 23, 2021
24-hour UTC period · USGS data
LARGEST: M5.2 — South Sandwich Islands region
112 km deep
Elevated activitycompared to daily average (~250/day)
Magnitude Breakdown
M5.0+
5
M4.0–4.9
33
M3.0–3.9
16
M2.0–2.9
58
M1.0–1.9
191
Activity Summary
303
Total earthquakes
~250
Daily average
Elevated
Activity level
5
M5.0+ events
Geographic Breakdown
By US State
Significant Earthquakes (M4.5+)
5.2
South Sandwich Islands region
00:34 UTC · 112.3 km deep
5.1
78 km ENE of Hinatuan, Philippines
23:08 UTC · 10.0 km deep
Felt by 3
5.1
14 km ENE of Hualien City, Taiwan
03:16 UTC · 10.0 km deep
Felt by 8
5.1
Rat Islands, Aleutian Islands, Alaska
03:10 UTC · 54.7 km deep
Felt by 1
5.0
South Sandwich Islands region
08:00 UTC · 54.2 km deep
4.9
Southwest Indian Ridge
14:17 UTC · 10.0 km deep
4.8
103 km SSW of Bengkulu, Indonesia
23:34 UTC · 46.5 km deep
4.8
79 km W of San Antonio de los Cobres, Argentina
08:21 UTC · 154.3 km deep
Earthquake Map — October 23, 2021
All Earthquakes — October 23, 2021
Showing 30 of 112 (filtered from 303)
(Filtered to M2.0+. Change the magnitude filter to see smaller events.)
| Time ↓ | Mag ↕ | Location ↕ | Depth ↕ | Felt ↕ | MMI | Alert | Status | Details |
|---|---|---|---|---|---|---|---|---|
2021-10-23 2021-10-23 23:55:45 UTC | 4.6mb | southern Mid-Atlantic Ridge -50.285°, -6.740° | 10.0 km | - | - | - | ✓ Reviewed | USGS → |
A magnitude 4.6 seismic event took place near southern Mid-Atlantic Ridge on October 23, 2021 at 23:55 UTC. See the M4.6 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2021-10-23 2021-10-23 23:43:01 UTC | 2.2md | 5km WNW of Walker, CA 38.525°, -119.536° | 3.8 km | - | - | - | ✓ Reviewed | USGS → |
A magnitude 2.2 seismic event took place 5km WNW of Walker, CA on October 23, 2021 at 23:43 UTC. This very shallow event was close enough to the surface that even modest magnitudes can produce significant local shaking. See the M2.2 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2021-10-23 2021-10-23 23:34:25 UTC | 4.8mb | 103 km SSW of Bengkulu, Indonesia -4.685°, 101.967° | 46.5 km | - | - | - | ✓ Reviewed | USGS → |
This magnitude 4.8 event was detected 103 km SSW of Bengkulu, Indonesia on October 23, 2021, with origin time 23:34 UTC. See the M4.8 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2021-10-23 2021-10-23 23:08:29 UTC | 5.1mb | 78 km ENE of Hinatuan, Philippines 8.565°, 127.016° | 10.0 km | 3 | - | - | ✓ Reviewed | USGS → |
A magnitude 5.1 earthquake was recorded 78 km ENE of Hinatuan, Philippines on October 23, 2021 at 23:08 UTC. See the M5.1 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2021-10-23 2021-10-23 23:02:32 UTC | 3.4ml | 115 km E of Chignik, Alaska 56.326°, -156.539° | 48.7 km | - | II | - | ✓ Reviewed | USGS → |
A magnitude 3.4 earthquake was recorded 115 km E of Chignik, Alaska on October 23, 2021 at 23:02 UTC. The event was offshore. See the M3.4 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2021-10-23 2021-10-23 22:47:27 UTC | 4.6mb | 36 km NW of Saint John’s, Antigua and Barbuda 17.306°, -62.127° | 94.0 km | 76 | - | - | ✓ Reviewed | USGS → |
October 23, 2021 brought a magnitude 4.6 earthquake 36 km NW of Saint John’s, Antigua and Barbuda, logged at 22:47 UTC. The event was offshore. See the M4.6 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2021-10-23 2021-10-23 22:04:51 UTC | 3.1md | 11 km NNE of San Antonio, Puerto Rico 18.593°, -67.076° | 78.0 km | - | - | - | ✓ Reviewed | USGS → |
A magnitude 3.1 earthquake was recorded 11 km NNE of San Antonio, Puerto Rico on October 23, 2021 at 22:04 UTC. See the M3.1 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2021-10-23 2021-10-23 21:55:11 UTC | 2.1ml | 19 km ENE of Georgetown, Idaho 42.531°, -111.139° | 5.8 km | - | - | - | ✓ Reviewed | USGS → |
Reports of a magnitude 2.1 earthquake 19 km ENE of Georgetown, Idaho came in on October 23, 2021 at 21:55 UTC. See the M2.1 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2021-10-23 2021-10-23 21:46:28 UTC | 3.1ml | 14km SSW of Loyalton, CA 39.563°, -120.313° | 6.0 km | 16 | - | - | ✓ Reviewed | USGS → |
Reports of a magnitude 3.1 earthquake 14km SSW of Loyalton, CA came in on October 23, 2021 at 21:46 UTC. See the M3.1 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2021-10-23 2021-10-23 21:24:47 UTC | 2.1ml | 3km SW of San Bernardino, CA 34.110°, -117.318° | 17.1 km | - | - | - | ✓ Reviewed | USGS → |
A magnitude 2.1 seismic event took place 3km SW of San Bernardino, CA on October 23, 2021 at 21:24 UTC. The event was offshore. See the M2.1 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2021-10-23 2021-10-23 21:22:58 UTC | 2.0ml | 56 km NW of Toyah, Texas 31.651°, -104.234° | 7.3 km | - | - | - | ✓ Reviewed | USGS → |
Seismographs logged a magnitude 2.0 earthquake 56 km NW of Toyah, Texas with origin time 21:22 UTC on October 23, 2021. It arrived roughly 13 hours after a larger magnitude 2.7 mainshock in the same 20 km area, placing it within the typical aftershock window. The event was offshore. See the M2.0 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2021-10-23 2021-10-23 21:12:55 UTC | 2.9ml | 28 km SE of Mina, Nevada 38.197°, -117.890° | 8.1 km | - | - | - | ✓ Reviewed | USGS → |
The USGS recorded this magnitude 2.9 earthquake 28 km SE of Mina, Nevada at 21:12 UTC on October 23, 2021. The event was offshore. See the M2.9 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2021-10-23 2021-10-23 20:58:36 UTC | 3.3ml | 114 km SSE of Sand Point, Alaska 54.413°, -159.731° | 10.9 km | - | - | - | ✓ Reviewed | USGS → |
Seismographs logged a magnitude 3.3 earthquake 114 km SSE of Sand Point, Alaska with origin time 20:58 UTC on October 23, 2021. See the M3.3 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2021-10-23 2021-10-23 19:59:13 UTC | 4.3mb | South Sandwich Islands region -60.123°, -29.906° | 10.0 km | - | - | - | ✓ Reviewed | USGS → |
A magnitude 4.3 earthquake was recorded in the South Sandwich Islands region on October 23, 2021 at 19:59 UTC. See the M4.3 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2021-10-23 2021-10-23 19:54:01 UTC | 4.2mb | 44 km NE of Imzouren, Morocco 35.396°, -3.473° | 10.0 km | - | - | - | ✓ Reviewed | USGS → |
Reports of a magnitude 4.2 earthquake 44 km NE of Imzouren, Morocco came in on October 23, 2021 at 19:54 UTC. The event was offshore. See the M4.2 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2021-10-23 2021-10-23 19:43:39 UTC | 4.1mb | 51 km NNE of Calama, Chile -22.053°, -68.666° | 120.7 km | - | - | - | ✓ Reviewed | USGS → |
A magnitude 4.1 earthquake was recorded 51 km NNE of Calama, Chile on October 23, 2021 at 19:43 UTC. See the M4.1 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2021-10-23 2021-10-23 19:38:57 UTC | 2.4ml | 9 km ENE of P?hala, Hawaii 19.238°, -155.396° | 32.8 km | - | - | - | Auto | USGS → |
On October 23, 2021 at 19:38 UTC, a magnitude 2.4 earthquake struck 9 km ENE of P?hala, Hawaii. Coming 4 hours after a magnitude 3.2 earthquake in the immediate vicinity, it is most likely an aftershock of that larger rupture. See the M2.4 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2021-10-23 2021-10-23 19:29:59 UTC | 2.5ml | 90 km SSE of Sand Point, Alaska 54.640°, -159.773° | 24.5 km | - | - | - | ✓ Reviewed | USGS → |
On October 23, 2021 at 19:29 UTC, a magnitude 2.5 earthquake struck 90 km SSE of Sand Point, Alaska. See the M2.5 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2021-10-23 2021-10-23 19:29:26 UTC | 2.2md | 2 km S of P?hala, Hawaii 19.180°, -155.474° | 37.4 km | - | - | - | Auto | USGS → |
On October 23, 2021, worldwide seismic activity registered a magnitude 2.2 earthquake 2 km S of P?hala, Hawaii at 19:29 UTC. It arrived roughly 16 hours after a larger magnitude 2.4 mainshock in the same 20 km area, placing it within the typical aftershock window. The event was offshore. See the M2.2 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2021-10-23 2021-10-23 19:09:09 UTC | 4.1mb | 296 km WSW of Tual, Indonesia -6.649°, 130.278° | 99.1 km | - | - | - | ✓ Reviewed | USGS → |
Seismographs logged a magnitude 4.1 earthquake 296 km WSW of Tual, Indonesia with origin time 19:09 UTC on October 23, 2021. See the M4.1 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2021-10-23 2021-10-23 19:01:32 UTC | 3.1ml | 19 km ESE of Wright, Wyoming 43.654°, -105.287° | 0.0 km | - | - | - | ✓ Reviewed | USGS → |
A magnitude 3.1 seismic event took place 19 km ESE of Wright, Wyoming on October 23, 2021 at 19:01 UTC. This very shallow event was close enough to the surface that even modest magnitudes can produce significant local shaking. See the M3.1 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2021-10-23 2021-10-23 18:51:48 UTC | 2.4ml | 79 km NW of Yakutat, Alaska 60.048°, -140.743° | 9.6 km | - | - | - | ✓ Reviewed | USGS → |
The USGS recorded this magnitude 2.4 earthquake 79 km NW of Yakutat, Alaska at 18:51 UTC on October 23, 2021. It arrived roughly 1 hours after a larger magnitude 2.5 mainshock in the same 20 km area, placing it within the typical aftershock window. The event was offshore. See the M2.4 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2021-10-23 2021-10-23 18:51:48 UTC | 2.5ml | 77 km NW of Yakutat, Alaska 60.005°, -140.770° | 4.8 km | - | - | - | Auto | USGS → |
A magnitude 2.5 earthquake was recorded 77 km NW of Yakutat, Alaska on October 23, 2021 at 18:51 UTC. This very shallow event was close enough to the surface that even modest magnitudes can produce significant local shaking. See the M2.5 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2021-10-23 2021-10-23 17:04:58 UTC | 2.0ml | 2 km NW of Lindsay, Texas 31.386°, -103.551° | 3.1 km | - | - | - | ✓ Reviewed | USGS → |
On October 23, 2021, worldwide seismic activity registered a magnitude 2.0 earthquake 2 km NW of Lindsay, Texas at 17:04 UTC. This very shallow event was close enough to the surface that even modest magnitudes can produce significant local shaking. See the M2.0 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2021-10-23 2021-10-23 16:49:43 UTC | 2.6ml | Rat Islands, Aleutian Islands, Alaska 51.389°, 178.777° | 35.0 km | - | - | - | ✓ Reviewed | USGS → |
A magnitude 2.6 seismic event took place near Rat Islands, Aleutian Islands, Alaska on October 23, 2021 at 16:49 UTC. Coming 11 hours after a magnitude 3.3 earthquake in the immediate vicinity, it is most likely an aftershock of that larger rupture. See the M2.6 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2021-10-23 2021-10-23 16:31:34 UTC | 2.0md | 3 km SSE of P?hala, Hawaii 19.174°, -155.464° | 35.6 km | - | - | - | Auto | USGS → |
A magnitude 2.0 earthquake was recorded 3 km SSE of P?hala, Hawaii on October 23, 2021 at 16:31 UTC. Coming 13 hours after a magnitude 2.4 earthquake in the immediate vicinity, it is most likely an aftershock of that larger rupture. See the M2.0 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2021-10-23 2021-10-23 16:29:17 UTC | 3.8md | 47 km SE of Boca de Yuma, Dominican Republic 18.119°, -68.254° | 92.0 km | - | - | - | ✓ Reviewed | USGS → |
A magnitude 3.8 seismic event took place 47 km SE of Boca de Yuma, Dominican Republic on October 23, 2021 at 16:29 UTC. The event was offshore. See the M3.8 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2021-10-23 2021-10-23 16:28:40 UTC | 4.4mb | off the east coast of the North Island of New Zealand -37.434°, 179.664° | 10.0 km | - | - | - | ✓ Reviewed | USGS → |
This magnitude 4.4 event was detected near off the east coast of the North Island of New Zealand on October 23, 2021, with origin time 16:28 UTC. See the M4.4 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2021-10-23 2021-10-23 16:28:35 UTC | 2.3md | 6km SSW of Gilroy, CA 36.955°, -121.591° | 3.8 km | 2 | - | - | ✓ Reviewed | USGS → |
This magnitude 2.3 event was detected 6km SSW of Gilroy, CA on October 23, 2021, with origin time 16:28 UTC. This very shallow event was close enough to the surface that even modest magnitudes can produce significant local shaking. See the M2.3 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2021-10-23 2021-10-23 16:26:50 UTC | 4.6mb | South Sandwich Islands region -58.904°, -24.888° | 10.0 km | - | - | - | ✓ Reviewed | USGS → |
On October 23, 2021 at 16:26 UTC, a magnitude 4.6 earthquake struck in the South Sandwich Islands region. See the M4.6 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
Legend:
Mag: Magnitude (magType = ml, mb, mw, etc.)
Felt: Number of DYFI felt reports
MMI: Modified Mercalli Intensity (I-X+)
Alert: PAGER alert level
Depth: Shallow (<70km), Intermediate, Deep (>300km)
Status: Auto = preliminary, Reviewed = verified by seismologist
Click any row to see additional technical details.
About This Page
This page shows all earthquakes recorded by the USGS Earthquake Hazards Program during the 24-hour UTC period on October 23, 2021. Data includes all events of magnitude 1.0 or greater. Past earthquake data is considered final after review by USGS seismologists.