Earthquakes on October 20, 2023
270
EARTHQUAKES on October 20, 2023
24-hour UTC period · USGS data
17 km deep
Normal activitycompared to daily average (~250/day)
Magnitude Breakdown
M5.0+
3
M4.0–4.9
38
M3.0–3.9
16
M2.0–2.9
45
M1.0–1.9
168
Activity Summary
270
Total earthquakes
~250
Daily average
Normal
Activity level
3
M5.0+ events
Significant Earthquakes (M4.5+)
5.7
172 km WSW of Merizo Village, Guam
00:04 UTC · 16.8 km deep
5.1
65 km SSE of Tondano, Indonesia
19:51 UTC · 61.2 km deep
Felt by 2
5.0
Izu Islands, Japan region
19:01 UTC · 28.8 km deep
4.9
114 km WSW of Puerto Madero, Mexico
23:00 UTC · 10.0 km deep
Felt by 1
4.9
101 km ENE of Masohi, Indonesia
07:57 UTC · 18.8 km deep
4.8
20 km ENE of Kimbe, Papua New Guinea
19:34 UTC · 130.3 km deep
4.8
158 km SSE of Teluk Dalam, Indonesia
18:01 UTC · 20.8 km deep
4.7
154 km SSW of Colonia, Micronesia
13:24 UTC · 10.0 km deep
Earthquake Map — October 20, 2023
All Earthquakes — October 20, 2023
Showing 30 of 102 (filtered from 270)
(Filtered to M2.0+. Change the magnitude filter to see smaller events.)
| Time ↓ | Mag ↕ | Location ↕ | Depth ↕ | Felt ↕ | MMI | Alert | Status | Details |
|---|---|---|---|---|---|---|---|---|
2023-10-20 2023-10-20 23:47:02 UTC | 4.0mb | Rat Islands, Aleutian Islands, Alaska 51.888°, 178.015° | 146.1 km | - | - | - | ✓ Reviewed | USGS → |
A magnitude 4.0 seismic event took place near Rat Islands, Aleutian Islands, Alaska on October 20, 2023 at 23:47 UTC. See the M4.0 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-20 2023-10-20 23:45:47 UTC | 2.2ml | 6 km SW of Falls City, Texas 28.934°, -98.061° | 5.2 km | - | - | - | ✓ Reviewed | USGS → |
A magnitude 2.2 earthquake was recorded 6 km SW of Falls City, Texas on October 20, 2023 at 23:45 UTC. It arrived roughly 1 hours after a larger magnitude 3.7 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. | ||||||||
2023-10-20 2023-10-20 23:14:39 UTC | 2.7ml | 106 km SSW of Nikolski, Alaska 52.068°, -169.500° | 35.0 km | - | - | - | ✓ Reviewed | USGS → |
A magnitude 2.7 earthquake was recorded 106 km SSW of Nikolski, Alaska on October 20, 2023 at 23:14 UTC. This event falls inside the aftershock decay of a nearby magnitude 4.5 earthquake that occurred about 4 hours earlier. See the M2.7 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-20 2023-10-20 23:09:31 UTC | 2.3ml | 7 km SSW of Falls City, Texas 28.928°, -98.054° | 7.4 km | - | - | - | ✓ Reviewed | USGS → |
A magnitude 2.3 earthquake was recorded 7 km SSW of Falls City, Texas on October 20, 2023 at 23:09 UTC. Coming 1 hours after a magnitude 3.7 earthquake in the immediate vicinity, it is most likely an aftershock of that larger rupture. See the M2.3 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-20 2023-10-20 23:08:37 UTC | 2.0ml | 21 km SE of Leilani Estates, Hawaii 19.329°, -154.775° | 41.2 km | - | - | - | ✓ Reviewed | USGS → |
This magnitude 2.0 event was detected 21 km SE of Leilani Estates, Hawaii on October 20, 2023, with origin time 23:08 UTC. The event was offshore. See the M2.0 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-20 2023-10-20 23:07:44 UTC | 4.4mb | Izu Islands, Japan region 31.011°, 141.540° | 10.0 km | - | - | - | ✓ Reviewed | USGS → |
At 23:07 UTC on October 20, 2023, a magnitude 4.4 tremor occurred in the Izu Islands, Japan region. It arrived roughly 4 hours after a larger magnitude 5.0 mainshock in the same 20 km area, placing it within the typical aftershock window. See the M4.4 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-20 2023-10-20 23:07:28 UTC | 3.7ml | 8 km SW of Falls City, Texas 28.923°, -98.067° | 7.0 km | 19 | IV | - | ✓ Reviewed | USGS → |
At 23:07 UTC on October 20, 2023, a magnitude 3.7 tremor occurred 8 km SW of Falls City, Texas. In the 72 hours after this event, the USGS recorded 3 smaller earthquakes within 20 km, consistent with an ongoing aftershock sequence rooted here. See the M3.7 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-20 2023-10-20 23:00:21 UTC | 4.9mww | 114 km WSW of Puerto Madero, Mexico 14.367°, -93.422° | 10.0 km | 1 | - | - | ✓ Reviewed | USGS → |
On October 20, 2023, worldwide seismic activity registered a magnitude 4.9 earthquake 114 km WSW of Puerto Madero, Mexico at 23:00 UTC. See the M4.9 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-20 2023-10-20 22:05:50 UTC | 2.2ml | 56 km SW of Nikolski, Alaska 52.625°, -169.519° | 30.3 km | - | - | - | ✓ Reviewed | USGS → |
Seismographs logged a magnitude 2.2 earthquake 56 km SW of Nikolski, Alaska with origin time 22:05 UTC on October 20, 2023. The event was offshore. See the M2.2 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-20 2023-10-20 22:04:15 UTC | 4.4mb | 113 km WSW of Puerto Madero, Mexico 14.298°, -93.379° | 10.0 km | - | - | - | ✓ Reviewed | USGS → |
The USGS recorded this magnitude 4.4 earthquake 113 km WSW of Puerto Madero, Mexico at 22:04 UTC on October 20, 2023. See the M4.4 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-20 2023-10-20 21:32:17 UTC | 2.2md | 6 km NNW of Pinnacles, CA 36.579°, -121.174° | 5.9 km | - | - | - | ✓ Reviewed | USGS → |
The USGS recorded this magnitude 2.2 earthquake 6 km NNW of Pinnacles, CA at 21:32 UTC on October 20, 2023. See the M2.2 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-20 2023-10-20 21:21:21 UTC | 4.6mb | 114 km ESE of Neiafu, Tonga -19.058°, -172.981° | 10.0 km | - | - | - | ✓ Reviewed | USGS → |
A magnitude 4.6 seismic event took place 114 km ESE of Neiafu, Tonga on October 20, 2023 at 21:21 UTC. See the M4.6 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-20 2023-10-20 21:15:14 UTC | 3.0ml | 207 km SE of Chiniak, Alaska 56.349°, -149.770° | 10.0 km | - | - | - | ✓ Reviewed | USGS → |
On October 20, 2023, worldwide seismic activity registered a magnitude 3.0 earthquake 207 km SE of Chiniak, Alaska at 21:15 UTC. The event was offshore. See the M3.0 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-20 2023-10-20 21:14:47 UTC | 2.3ml | 11 km E of Pāhala, Hawaii 19.189°, -155.374° | -0.6 km | - | - | - | Auto | USGS → |
October 20, 2023 brought a magnitude 2.3 earthquake 11 km E of Pāhala, Hawaii, logged at 21:14 UTC. This event falls inside the aftershock decay of a nearby magnitude 3.5 earthquake that occurred about 18 hours earlier. 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. | ||||||||
2023-10-20 2023-10-20 21:11:58 UTC | 2.6md | 8 km ENE of Alum Rock, CA 37.389°, -121.739° | 6.7 km | 12 | - | - | ✓ Reviewed | USGS → |
Seismographs logged a magnitude 2.6 earthquake 8 km ENE of Alum Rock, CA with origin time 21:11 UTC on October 20, 2023. See the M2.6 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-20 2023-10-20 21:06:13 UTC | 2.1ml | Rat Islands, Aleutian Islands, Alaska 51.962°, 178.440° | 4.8 km | - | - | - | ✓ Reviewed | USGS → |
On October 20, 2023 at 21:06 UTC, a magnitude 2.1 earthquake struck near Rat Islands, Aleutian Islands, Alaska. This very shallow event was close enough to the surface that even modest magnitudes can produce significant local shaking. See the M2.1 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-20 2023-10-20 20:55:29 UTC | 4.5mb | 29 km ESE of Iwaki, Japan 36.948°, 141.183° | 36.4 km | - | - | - | ✓ Reviewed | USGS → |
This magnitude 4.5 event was detected 29 km ESE of Iwaki, Japan on October 20, 2023, with origin time 20:55 UTC. See the M4.5 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-20 2023-10-20 20:54:48 UTC | 4.1mb | 26 km NNE of Atka, Alaska 52.409°, -174.039° | 119.5 km | - | II | - | ✓ Reviewed | USGS → |
This magnitude 4.1 event was detected 26 km NNE of Atka, Alaska on October 20, 2023, with origin time 20:54 UTC. See the M4.1 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-20 2023-10-20 20:50:14 UTC | 3.0md | 55 km W of Petrolia, CA 40.370°, -124.936° | 12.4 km | 1 | - | - | ✓ Reviewed | USGS → |
Reports of a magnitude 3.0 earthquake 55 km W of Petrolia, CA came in on October 20, 2023 at 20:50 UTC. The event was offshore. See the M3.0 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-20 2023-10-20 20:14:39 UTC | 3.0ml | 20 km WSW of Anchor Point, Alaska 59.706°, -152.173° | 68.9 km | - | - | - | ✓ Reviewed | USGS → |
At 20:14 UTC on October 20, 2023, a magnitude 3.0 tremor occurred 20 km WSW of Anchor Point, Alaska. See the M3.0 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-20 2023-10-20 19:55:25 UTC | 2.4ml | Southeastern Alaska 59.465°, -138.883° | 16.4 km | - | - | - | ✓ Reviewed | USGS → |
Reports of a magnitude 2.4 earthquake near Southeastern Alaska came in on October 20, 2023 at 19:55 UTC. See the M2.4 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-20 2023-10-20 19:51:56 UTC | 5.1mb | 65 km SSE of Tondano, Indonesia 0.789°, 125.206° | 61.2 km | 2 | - | - | ✓ Reviewed | USGS → |
A magnitude 5.1 earthquake was recorded 65 km SSE of Tondano, Indonesia on October 20, 2023 at 19:51 UTC. See the M5.1 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-20 2023-10-20 19:45:30 UTC | 2.8md | Puerto Rico region 17.937°, -66.944° | 10.9 km | - | - | - | ✓ Reviewed | USGS → |
A magnitude 2.8 seismic event took place in the Puerto Rico region on October 20, 2023 at 19:45 UTC. See the M2.8 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-20 2023-10-20 19:39:39 UTC | 4.5mb | 87 km SSW of Nikolski, Alaska 52.232°, -169.430° | 20.9 km | - | II | - | ✓ Reviewed | USGS → |
Reports of a magnitude 4.5 earthquake 87 km SSW of Nikolski, Alaska came in on October 20, 2023 at 19:39 UTC. See the M4.5 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-20 2023-10-20 19:34:03 UTC | 4.8mb | 20 km ENE of Kimbe, Papua New Guinea -5.512°, 150.320° | 130.3 km | - | - | - | ✓ Reviewed | USGS → |
The USGS recorded this magnitude 4.8 earthquake 20 km ENE of Kimbe, Papua New Guinea at 19:34 UTC on October 20, 2023. See the M4.8 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-20 2023-10-20 19:16:10 UTC | 4.6mb | Izu Islands, Japan region 30.939°, 141.363° | 31.4 km | - | - | - | ✓ Reviewed | USGS → |
October 20, 2023 brought a magnitude 4.6 earthquake in the Izu Islands, Japan region, logged at 19:16 UTC. It arrived roughly 1 hours after a larger magnitude 5.0 mainshock in the same 20 km area, placing it within the typical aftershock window. See the M4.6 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-20 2023-10-20 19:16:03 UTC | 3.4ml | 89 km S of Unalaska, Alaska 53.086°, -166.781° | 35.0 km | - | - | - | ✓ Reviewed | USGS → |
This magnitude 3.4 event was detected 89 km S of Unalaska, Alaska on October 20, 2023, with origin time 19:16 UTC. The event was offshore. See the M3.4 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-20 2023-10-20 19:13:53 UTC | 3.3ml | 106 km SSW of Nikolski, Alaska 52.058°, -169.488° | 32.9 km | - | - | - | ✓ Reviewed | USGS → |
A magnitude 3.3 seismic event took place 106 km SSW of Nikolski, Alaska on October 20, 2023 at 19:13 UTC. It arrived roughly 2 hours after a larger magnitude 3.8 mainshock in the same 20 km area, placing it within the typical aftershock window. See the M3.3 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-20 2023-10-20 19:01:44 UTC | 5.0mww | Izu Islands, Japan region 30.940°, 141.365° | 28.8 km | - | - | - | ✓ Reviewed | USGS → |
Seismographs logged a magnitude 5.0 earthquake in the Izu Islands, Japan region with origin time 19:01 UTC on October 20, 2023. See the M5.0 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-20 2023-10-20 18:34:28 UTC | 4.5mb | 23 km E of Curahuara de Carangas, Bolivia -17.903°, -68.217° | 208.3 km | - | - | - | ✓ Reviewed | USGS → |
A magnitude 4.5 seismic event took place 23 km E of Curahuara de Carangas, Bolivia on October 20, 2023 at 18:34 UTC. The event was offshore. See the M4.5 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 20, 2023. Data includes all events of magnitude 1.0 or greater. Past earthquake data is considered final after review by USGS seismologists.