Time ↓	Mag ↕	Location ↕	Depth ↕	Felt ↕	MMI	Alert	Status	Details
2021-09-04 2021-09-04 23:41:38 UTC	4.9mb	167 km WNW of Panguna, Papua New Guinea -5.489°, 154.220°	165.8 km	-	-	-	✓ Reviewed	USGS →
At 23:41 UTC on September 4, 2021, a magnitude 4.9 tremor occurred 167 km WNW of Panguna, Papua New Guinea. See the M4.9 event page for the full report, ShakeMap, and citizen-reported intensity data.
2021-09-04 2021-09-04 23:38:08 UTC	2.5ml	21 km W of Volcano, Hawaii 19.469°, -155.441°	7.3 km	-	-	-	✓ Reviewed	USGS →
On September 4, 2021, worldwide seismic activity registered a magnitude 2.5 earthquake 21 km W of Volcano, Hawaii at 23:38 UTC. Coming 21 hours after a magnitude 2.5 earthquake in the immediate vicinity, it is most likely an aftershock of that larger rupture. The event was offshore. See the M2.5 event page for the full report, ShakeMap, and citizen-reported intensity data.
2021-09-04 2021-09-04 23:31:55 UTC	4.6mb	South Sandwich Islands region -59.457°, -26.000°	35.0 km	-	-	-	✓ Reviewed	USGS →
At 23:31 UTC on September 4, 2021, a magnitude 4.6 tremor occurred in the South Sandwich Islands region. See the M4.6 event page for the full report, ShakeMap, and citizen-reported intensity data.
2021-09-04 2021-09-04 23:24:36 UTC	2.5ml	55 km S of Whites City, New Mexico 31.672°, -104.368°	6.2 km	-	-	-	✓ Reviewed	USGS →
This magnitude 2.5 event was detected 55 km S of Whites City, New Mexico on September 4, 2021, with origin time 23:24 UTC. The event was offshore. See the M2.5 event page for the full report, ShakeMap, and citizen-reported intensity data.
2021-09-04 2021-09-04 23:08:12 UTC	3.1ml	19 km E of Balmorhea, Texas 30.990°, -103.539°	4.9 km	-	-	-	✓ Reviewed	USGS →
Seismographs logged a magnitude 3.1 earthquake 19 km E of Balmorhea, Texas with origin time 23:08 UTC on September 4, 2021. 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.
2021-09-04 2021-09-04 23:05:21 UTC	2.3ml	32 km W of Salamatof, Alaska 60.571°, -151.907°	75.3 km	-	-	-	✓ Reviewed	USGS →
September 4, 2021 brought a magnitude 2.3 earthquake 32 km W of Salamatof, Alaska, logged at 23:05 UTC. The event was offshore. See the M2.3 event page for the full report, ShakeMap, and citizen-reported intensity data.
2021-09-04 2021-09-04 23:03:08 UTC	5.2mww	116 km SSW of Merizo Village, Guam 12.265°, 144.340°	8.7 km	2	-	-	✓ Reviewed	USGS →
A magnitude 5.2 earthquake was recorded 116 km SSW of Merizo Village, Guam on September 4, 2021 at 23:03 UTC. See the M5.2 event page for the full report, ShakeMap, and citizen-reported intensity data.
2021-09-04 2021-09-04 22:32:03 UTC	4.0mb	Kermadec Islands region -31.528°, -179.364°	111.0 km	-	-	-	✓ Reviewed	USGS →
On September 4, 2021, worldwide seismic activity registered a magnitude 4.0 earthquake in the Kermadec Islands region at 22:32 UTC. See the M4.0 event page for the full report, ShakeMap, and citizen-reported intensity data.
2021-09-04 2021-09-04 22:30:17 UTC	2.7ml	Rat Islands, Aleutian Islands, Alaska 50.873°, 178.103°	10.0 km	-	-	-	✓ Reviewed	USGS →
Reports of a magnitude 2.7 earthquake near Rat Islands, Aleutian Islands, Alaska came in on September 4, 2021 at 22:30 UTC. See the M2.7 event page for the full report, ShakeMap, and citizen-reported intensity data.
2021-09-04 2021-09-04 21:53:34 UTC	4.6mb	southern East Pacific Rise -24.389°, -115.734°	10.0 km	-	-	-	✓ Reviewed	USGS →
The USGS recorded this magnitude 4.6 earthquake near southern East Pacific Rise at 21:53 UTC on September 4, 2021. See the M4.6 event page for the full report, ShakeMap, and citizen-reported intensity data.
2021-09-04 2021-09-04 21:51:39 UTC	2.8md	Puerto Rico region 17.858°, -66.852°	10.0 km	-	-	-	✓ Reviewed	USGS →
On September 4, 2021 at 21:51 UTC, a magnitude 2.8 earthquake struck in the Puerto Rico region. It arrived roughly 17 hours after a larger magnitude 3.0 mainshock in the same 20 km area, placing it within the typical aftershock window. See the M2.8 event page for the full report, ShakeMap, and citizen-reported intensity data.
2021-09-04 2021-09-04 21:22:58 UTC	3.0ml	76 km SE of King Cove, Alaska 54.636°, -161.373°	33.4 km	-	-	-	✓ Reviewed	USGS →
The USGS recorded this magnitude 3.0 earthquake 76 km SE of King Cove, Alaska at 21:22 UTC on September 4, 2021. The event was offshore. See the M3.0 event page for the full report, ShakeMap, and citizen-reported intensity data.
2021-09-04 2021-09-04 21:17:55 UTC	2.7ml	6 km NNE of Alex, Oklahoma 34.974°, -97.758°	7.6 km	4	-	-	✓ Reviewed	USGS →
The USGS recorded this magnitude 2.7 earthquake 6 km NNE of Alex, Oklahoma at 21:17 UTC on September 4, 2021. See the M2.7 event page for the full report, ShakeMap, and citizen-reported intensity data.
2021-09-04 2021-09-04 21:06:22 UTC	2.6md	14 km SSE of Guánica, Puerto Rico 17.848°, -66.855°	7.0 km	-	-	-	✓ Reviewed	USGS →
On September 4, 2021 at 21:06 UTC, a magnitude 2.6 earthquake struck 14 km SSE of Guánica, Puerto Rico. This event falls inside the aftershock decay of a nearby magnitude 3.0 earthquake that occurred about 16 hours earlier. See the M2.6 event page for the full report, ShakeMap, and citizen-reported intensity data.
2021-09-04 2021-09-04 21:01:18 UTC	2.4ml	1 km SE of P?hala, Hawaii 19.194°, -155.466°	35.3 km	-	-	-	Auto	USGS →
The USGS recorded this magnitude 2.4 earthquake 1 km SE of P?hala, Hawaii at 21:01 UTC on September 4, 2021. This event falls inside the aftershock decay of a nearby magnitude 2.6 earthquake that occurred about 9 hours earlier. The event was offshore. See the M2.4 event page for the full report, ShakeMap, and citizen-reported intensity data.
2021-09-04 2021-09-04 20:57:25 UTC	4.0mb	off the coast of Oregon 43.994°, -129.089°	10.0 km	6	-	-	✓ Reviewed	USGS →
At 20:57 UTC on September 4, 2021, a magnitude 4.0 tremor occurred near off the coast of Oregon. See the M4.0 event page for the full report, ShakeMap, and citizen-reported intensity data.
2021-09-04 2021-09-04 20:50:25 UTC	2.1ml	87 km WSW of Elfin Cove, Alaska 57.935°, -137.738°	9.9 km	-	-	-	✓ Reviewed	USGS →
A magnitude 2.1 earthquake was recorded 87 km WSW of Elfin Cove, Alaska on September 4, 2021 at 20:50 UTC. See the M2.1 event page for the full report, ShakeMap, and citizen-reported intensity data.
2021-09-04 2021-09-04 20:44:32 UTC	2.0md	4 km E of P?hala, Hawaii 19.210°, -155.440°	33.2 km	-	-	-	Auto	USGS →
At 20:44 UTC on September 4, 2021, a magnitude 2.0 tremor occurred 4 km E of P?hala, Hawaii. This event falls inside the aftershock decay of a nearby magnitude 2.6 earthquake that occurred about 9 hours earlier. The event was offshore. See the M2.0 event page for the full report, ShakeMap, and citizen-reported intensity data.
2021-09-04 2021-09-04 20:18:13 UTC	2.6ml	197 km SE of Akutan, Alaska 52.721°, -163.984°	20.3 km	-	-	-	✓ Reviewed	USGS →
Seismographs logged a magnitude 2.6 earthquake 197 km SE of Akutan, Alaska with origin time 20:18 UTC on September 4, 2021. The event was offshore. See the M2.6 event page for the full report, ShakeMap, and citizen-reported intensity data.
2021-09-04 2021-09-04 20:16:05 UTC	4.6mb	92 km NNE of Hihifo, Tonga -15.137°, -173.622°	10.0 km	-	-	-	✓ Reviewed	USGS →
This magnitude 4.6 event was detected 92 km NNE of Hihifo, Tonga on September 4, 2021, with origin time 20:16 UTC. See the M4.6 event page for the full report, ShakeMap, and citizen-reported intensity data.
2021-09-04 2021-09-04 20:03:55 UTC	4.3mb	168 km NNW of Jiangyou, China 33.084°, 103.816°	10.0 km	-	-	-	✓ Reviewed	USGS →
September 4, 2021 brought a magnitude 4.3 earthquake 168 km NNW of Jiangyou, China, logged at 20:03 UTC. See the M4.3 event page for the full report, ShakeMap, and citizen-reported intensity data.
2021-09-04 2021-09-04 19:53:42 UTC	2.0md	4 km E of P?hala, Hawaii 19.198°, -155.434°	36.2 km	-	-	-	Auto	USGS →
A magnitude 2.0 earthquake was recorded 4 km E of P?hala, Hawaii on September 4, 2021 at 19:53 UTC. This event falls inside the aftershock decay of a nearby magnitude 2.6 earthquake that occurred about 8 hours earlier. The event was offshore. See the M2.0 event page for the full report, ShakeMap, and citizen-reported intensity data.
2021-09-04 2021-09-04 19:32:41 UTC	4.3mb	South Sandwich Islands region -57.882°, -24.127°	10.0 km	-	-	-	✓ Reviewed	USGS →
On September 4, 2021 at 19:32 UTC, a magnitude 4.3 earthquake struck in the South Sandwich Islands region. See the M4.3 event page for the full report, ShakeMap, and citizen-reported intensity data.
2021-09-04 2021-09-04 19:31:29 UTC	3.3ml	295 km S of Akhiok, Alaska 54.325°, -153.407°	10.0 km	-	-	-	✓ Reviewed	USGS →
A magnitude 3.3 seismic event took place 295 km S of Akhiok, Alaska on September 4, 2021 at 19:31 UTC. The event was offshore. See the M3.3 event page for the full report, ShakeMap, and citizen-reported intensity data.
2021-09-04 2021-09-04 19:10:01 UTC	2.5ml	88 km ESE of Adak, Alaska 51.708°, -175.374°	58.0 km	-	-	-	✓ Reviewed	USGS →
Reports of a magnitude 2.5 earthquake 88 km ESE of Adak, Alaska came in on September 4, 2021 at 19:10 UTC. See the M2.5 event page for the full report, ShakeMap, and citizen-reported intensity data.
2021-09-04 2021-09-04 18:58:16 UTC	4.3mb	Baffin Bay 73.240°, -72.936°	16.0 km	1	-	-	✓ Reviewed	USGS →
A magnitude 4.3 earthquake was recorded near Baffin Bay on September 4, 2021 at 18:58 UTC. See the M4.3 event page for the full report, ShakeMap, and citizen-reported intensity data.
2021-09-04 2021-09-04 18:43:39 UTC	5.4mww	62 km W of Panguna, Papua New Guinea -6.398°, 154.924°	60.6 km	2	IV	green	✓ Reviewed	USGS →
On September 4, 2021 at 18:43 UTC, a magnitude 5.4 earthquake struck 62 km W of Panguna, Papua New Guinea. The USGS PAGER system assigned a green alert level for this event, signalling no significant casualties or damage expected. It is the largest earthquake currently listed for worldwide seismic activity on September 4, 2021. See the M5.4 event page for the full report, ShakeMap, and citizen-reported intensity data.
2021-09-04 2021-09-04 18:11:55 UTC	2.3ml	24 km WNW of Mentasta Lake, Alaska 63.033°, -144.180°	5.1 km	-	-	-	✓ Reviewed	USGS →
On September 4, 2021 at 18:11 UTC, a magnitude 2.3 earthquake struck 24 km WNW of Mentasta Lake, Alaska. See the M2.3 event page for the full report, ShakeMap, and citizen-reported intensity data.
2021-09-04 2021-09-04 17:58:13 UTC	4.2mb	279 km NW of Haveluloto, Tonga -19.618°, -177.341°	562.6 km	-	-	-	✓ Reviewed	USGS →
The USGS recorded this magnitude 4.2 earthquake 279 km NW of Haveluloto, Tonga at 17:58 UTC on September 4, 2021. This deep-focus earthquake originated far below the brittle crust, deep inside the mantle. See the M4.2 event page for the full report, ShakeMap, and citizen-reported intensity data.
2021-09-04 2021-09-04 17:55:25 UTC	4.5mb	92 km NW of Zangguy, China 37.769°, 77.918°	10.0 km	-	-	-	✓ Reviewed	USGS →
A magnitude 4.5 earthquake was recorded 92 km NW of Zangguy, China on September 4, 2021 at 17:55 UTC. It arrived roughly 16 hours after a larger magnitude 4.8 mainshock in the same 20 km area, placing it within the typical aftershock window. 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 September 4, 2021. Data includes all events of magnitude 1.0 or greater. Past earthquake data is considered final after review by USGS seismologists.

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