Earthquakes on October 16, 2023
263
EARTHQUAKES on October 16, 2023
24-hour UTC period · USGS data
LARGEST: M6.4 — 78 km NNW of Adak, Alaska
174 km deep · 12 people felt it
Normal activitycompared to daily average (~250/day)
Magnitude Breakdown
M5.0+
5
M4.0–4.9
40
M3.0–3.9
7
M2.0–2.9
63
M1.0–1.9
148
Activity Summary
263
Total earthquakes
~250
Daily average
Normal
Activity level
5
M5.0+ events
Geographic Breakdown
By US State
Top Countries (International)
Significant Earthquakes (M4.5+)
6.4
78 km NNW of Adak, Alaska
11:35 UTC · 174.0 km deep
Felt by 12
5.7
46 km NNE of Hirara, Japan
10:42 UTC · 13.3 km deep
5.2
126 km ENE of Labasa, Fiji
08:46 UTC · 10.0 km deep
Felt by 5
5.2
113 km ENE of Petropavlovsk-Kamchatsky, Russia
06:48 UTC · 62.4 km deep
Felt by 1
5.0
78 km WSW of San Antonio de los Cobres, Argentina
18:33 UTC · 172.6 km deep
4.9
39 km NNE of Hirara, Japan
13:30 UTC · 9.5 km deep
4.9
Kermadec Islands region
06:33 UTC · 45.1 km deep
4.8
20 km E of Petrolia, CA
10:20 UTC · 31.1 km deep
Felt by 731
Earthquake Map — October 16, 2023
All Earthquakes — October 16, 2023
Showing 30 of 115 (filtered from 263)
(Filtered to M2.0+. Change the magnitude filter to see smaller events.)
| Time ↓ | Mag ↕ | Location ↕ | Depth ↕ | Felt ↕ | MMI | Alert | Status | Details |
|---|---|---|---|---|---|---|---|---|
2023-10-16 2023-10-16 23:52:15 UTC | 2.0md | 1 km SW of Pāhala, Hawaii 19.191°, -155.492° | 33.6 km | - | - | - | Auto | USGS → |
The USGS recorded this magnitude 2.0 earthquake 1 km SW of Pāhala, Hawaii at 23:52 UTC on October 16, 2023. It arrived roughly 22 hours after a larger magnitude 2.2 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. | ||||||||
2023-10-16 2023-10-16 23:48:24 UTC | 2.2md | 0 km ESE of Clio, CA 39.744°, -120.568° | 3.2 km | - | - | - | ✓ Reviewed | USGS → |
On October 16, 2023 at 23:48 UTC, a magnitude 2.2 earthquake struck 0 km ESE of Clio, CA. 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. | ||||||||
2023-10-16 2023-10-16 23:48:08 UTC | 2.2ml | 12 km S of Honoka‘a, Hawaii 19.963°, -155.469° | 39.8 km | - | - | - | ✓ Reviewed | USGS → |
The USGS recorded this magnitude 2.2 earthquake 12 km S of Honoka‘a, Hawaii at 23:48 UTC on October 16, 2023. The event was offshore. See the M2.2 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-16 2023-10-16 23:26:04 UTC | 4.1ml | 6 km WNW of Santiago, Costa Rica 9.870°, -84.370° | 12.7 km | 2 | - | - | ✓ Reviewed | USGS → |
A magnitude 4.1 earthquake was recorded 6 km WNW of Santiago, Costa Rica on October 16, 2023 at 23:26 UTC. See the M4.1 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-16 2023-10-16 23:13:31 UTC | 4.5mb | 289 km SSE of Port Blair, India 9.370°, 94.010° | 10.3 km | - | - | - | ✓ Reviewed | USGS → |
This magnitude 4.5 event was detected 289 km SSE of Port Blair, India on October 16, 2023, with origin time 23:13 UTC. See the M4.5 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-16 2023-10-16 22:56:08 UTC | 2.1md | 31 km WSW of Round Valley, CA 37.349°, -118.936° | 13.7 km | - | - | - | ✓ Reviewed | USGS → |
A magnitude 2.1 earthquake was recorded 31 km WSW of Round Valley, CA on October 16, 2023 at 22:56 UTC. See the M2.1 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-16 2023-10-16 22:43:10 UTC | 3.0ml | 286 km WSW of Adak, Alaska 51.424°, 179.285° | 30.9 km | - | - | - | ✓ Reviewed | USGS → |
On October 16, 2023 at 22:43 UTC, a magnitude 3.0 earthquake struck 286 km WSW of Adak, Alaska. See the M3.0 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-16 2023-10-16 22:24:54 UTC | 4.5mb | Mariana Islands region 17.959°, 147.403° | 10.0 km | - | - | - | ✓ Reviewed | USGS → |
Reports of a magnitude 4.5 earthquake in the Mariana Islands region came in on October 16, 2023 at 22:24 UTC. See the M4.5 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-16 2023-10-16 21:21:53 UTC | 2.7ml | Kodiak Island region, Alaska 56.705°, -152.577° | 3.4 km | - | - | - | ✓ Reviewed | USGS → |
On October 16, 2023 at 21:21 UTC, a magnitude 2.7 earthquake struck in the Kodiak Island region, Alaska. This very shallow event was close enough to the surface that even modest magnitudes can produce significant local shaking. See the M2.7 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-16 2023-10-16 21:10:28 UTC | 2.7ml | Kodiak Island region, Alaska 56.549°, -152.260° | 7.8 km | - | - | - | ✓ Reviewed | USGS → |
A magnitude 2.7 earthquake was recorded in the Kodiak Island region, Alaska on October 16, 2023 at 21:10 UTC. See the M2.7 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-16 2023-10-16 21:00:29 UTC | 2.9ml | 32 km SSW of Birney, Montana 45.054°, -106.687° | 0.0 km | - | - | - | ✓ Reviewed | USGS → |
The USGS recorded this magnitude 2.9 earthquake 32 km SSW of Birney, Montana at 21:00 UTC on October 16, 2023. This very shallow event was close enough to the surface that even modest magnitudes can produce significant local shaking. See the M2.9 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-16 2023-10-16 20:50:01 UTC | 4.6mb | 47 km NNE of Hirara, Japan 25.188°, 125.510° | 16.7 km | - | - | - | ✓ Reviewed | USGS → |
A magnitude 4.6 earthquake was recorded 47 km NNE of Hirara, Japan on October 16, 2023 at 20:50 UTC. Coming 10 hours after a magnitude 5.7 earthquake in the immediate vicinity, it is most likely an aftershock of that larger rupture. See the M4.6 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-16 2023-10-16 20:15:54 UTC | 2.2md | 5 km WSW of Guánica, Puerto Rico 17.959°, -66.955° | 11.2 km | - | - | - | ✓ Reviewed | USGS → |
Reports of a magnitude 2.2 earthquake 5 km WSW of Guánica, Puerto Rico came in on October 16, 2023 at 20:15 UTC. It arrived roughly 5 hours after a larger magnitude 3.0 mainshock in the same 20 km area, placing it within the typical aftershock window. See the M2.2 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-16 2023-10-16 20:05:40 UTC | 4.4mb | 290 km N of Saipan, Northern Mariana Islands 17.833°, 145.534° | 193.5 km | - | - | - | ✓ Reviewed | USGS → |
A magnitude 4.4 seismic event took place 290 km N of Saipan, Northern Mariana Islands on October 16, 2023 at 20:05 UTC. The event was offshore. See the M4.4 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-16 2023-10-16 19:55:01 UTC | 2.2md | 5 km NW of Friant, CA 37.014°, -119.764° | 8.9 km | 1 | - | - | ✓ Reviewed | USGS → |
On October 16, 2023, worldwide seismic activity registered a magnitude 2.2 earthquake 5 km NW of Friant, CA at 19:55 UTC. The event was offshore. See the M2.2 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-16 2023-10-16 19:49:52 UTC | 2.9ml | 21 km W of Volcano, Hawaii 19.467°, -155.440° | 6.8 km | - | - | - | ✓ Reviewed | USGS → |
Reports of a magnitude 2.9 earthquake 21 km W of Volcano, Hawaii came in on October 16, 2023 at 19:49 UTC. The event was offshore. See the M2.9 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-16 2023-10-16 18:57:41 UTC | 2.2md | 12 km SSE of Maria Antonia, Puerto Rico 17.876°, -66.850° | 14.9 km | - | - | - | ✓ Reviewed | USGS → |
At 18:57 UTC on October 16, 2023, a magnitude 2.2 tremor occurred 12 km SSE of Maria Antonia, Puerto Rico. This event falls inside the aftershock decay of a nearby magnitude 3.0 earthquake that occurred about 4 hours earlier. See the M2.2 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-16 2023-10-16 18:49:03 UTC | 4.3mwr | 65 km S of Vinchina, Argentina -29.350°, -68.258° | 35.0 km | - | - | - | ✓ Reviewed | USGS → |
The USGS recorded this magnitude 4.3 earthquake 65 km S of Vinchina, Argentina at 18:49 UTC on October 16, 2023. The event was offshore. See the M4.3 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-16 2023-10-16 18:48:04 UTC | 2.6ml | 23 km SSW of Newport Beach, CA 33.428°, -118.019° | 1.0 km | 2 | - | - | ✓ Reviewed | USGS → |
October 16, 2023 brought a magnitude 2.6 earthquake 23 km SSW of Newport Beach, CA, logged at 18:48 UTC. This very shallow event was close enough to the surface that even modest magnitudes can produce significant local shaking. See the M2.6 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-16 2023-10-16 18:33:19 UTC | 5.0mww | 78 km WSW of San Antonio de los Cobres, Argentina -24.521°, -67.018° | 172.6 km | - | - | - | ✓ Reviewed | USGS → |
At 18:33 UTC on October 16, 2023, a magnitude 5.0 tremor occurred 78 km WSW of San Antonio de los Cobres, Argentina. See the M5.0 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-16 2023-10-16 18:26:35 UTC | 2.1ml | 12 km ENE of Pāhala, Hawaii 19.249°, -155.365° | 30.5 km | - | - | - | Auto | USGS → |
Reports of a magnitude 2.1 earthquake 12 km ENE of Pāhala, Hawaii came in on October 16, 2023 at 18:26 UTC. This event falls inside the aftershock decay of a nearby magnitude 2.2 earthquake that occurred about 16 hours earlier. See the M2.1 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-16 2023-10-16 17:59:04 UTC | 2.0ml | 27 km NW of Susitna, Alaska 61.688°, -150.936° | 55.0 km | - | - | - | ✓ Reviewed | USGS → |
Reports of a magnitude 2.0 earthquake 27 km NW of Susitna, Alaska came in on October 16, 2023 at 17:59 UTC. The event was offshore. See the M2.0 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-16 2023-10-16 17:54:28 UTC | 2.0ml | 7 km ESE of North Shore, CA 33.507°, -115.862° | 4.7 km | - | - | - | ✓ Reviewed | USGS → |
At 17:54 UTC on October 16, 2023, a magnitude 2.0 tremor occurred 7 km ESE of North Shore, CA. 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. | ||||||||
2023-10-16 2023-10-16 17:49:26 UTC | 2.6ml(texnet) | western Texas 32.686°, -100.691° | 5.7 km | - | - | - | ✓ Reviewed | USGS → |
This magnitude 2.6 event was detected near western Texas on October 16, 2023, with origin time 17:49 UTC. See the M2.6 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-16 2023-10-16 17:36:41 UTC | 2.3md | 6 km SE of Maria Antonia, Puerto Rico 17.929°, -66.848° | 18.8 km | - | - | - | ✓ Reviewed | USGS → |
At 17:36 UTC on October 16, 2023, a magnitude 2.3 tremor occurred 6 km SE of Maria Antonia, Puerto Rico. It arrived roughly 2 hours after a larger magnitude 3.0 mainshock in the same 20 km area, placing it within the typical aftershock window. The event was offshore. See the M2.3 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-16 2023-10-16 17:32:43 UTC | 4.3mb | 205 km SE of Kokopo, Papua New Guinea -5.737°, 153.495° | 10.0 km | - | - | - | ✓ Reviewed | USGS → |
This magnitude 4.3 event was detected 205 km SE of Kokopo, Papua New Guinea on October 16, 2023, with origin time 17:32 UTC. The event was offshore. See the M4.3 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-16 2023-10-16 17:22:53 UTC | 4.6mb | Volcano Islands, Japan region 23.525°, 142.122° | 116.2 km | - | - | - | ✓ Reviewed | USGS → |
Seismographs logged a magnitude 4.6 earthquake in the Volcano Islands, Japan region with origin time 17:22 UTC on October 16, 2023. See the M4.6 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-16 2023-10-16 16:56:06 UTC | 2.9ml | 17 km WSW of Birney, Montana 45.283°, -106.736° | 0.0 km | - | - | - | ✓ Reviewed | USGS → |
This magnitude 2.9 event was detected 17 km WSW of Birney, Montana on October 16, 2023, with origin time 16:56 UTC. This very shallow event was close enough to the surface that even modest magnitudes can produce significant local shaking. See the M2.9 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-16 2023-10-16 16:14:22 UTC | 2.3md | 1 km W of Indios, Puerto Rico 17.995°, -66.832° | 15.9 km | - | - | - | ✓ Reviewed | USGS → |
October 16, 2023 brought a magnitude 2.3 earthquake 1 km W of Indios, Puerto Rico, logged at 16:14 UTC. This event falls inside the aftershock decay of a nearby magnitude 3.0 earthquake that occurred about 1 hours earlier. The event was offshore. See the M2.3 event page for the full report, ShakeMap, and citizen-reported intensity data. | ||||||||
2023-10-16 2023-10-16 16:05:08 UTC | 2.2ml | 3 km SSW of Pāhala, Hawaii 19.170°, -155.492° | 30.8 km | - | - | - | Auto | USGS → |
A magnitude 2.2 seismic event took place 3 km SSW of Pāhala, Hawaii on October 16, 2023 at 16:05 UTC. This event falls inside the aftershock decay of a nearby magnitude 2.2 earthquake that occurred about 14 hours earlier. See the M2.2 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 16, 2023. Data includes all events of magnitude 1.0 or greater. Past earthquake data is considered final after review by USGS seismologists.