Earthquake · reviewed by a seismologist
M 1.9md
Earthquake near Aibonito, PR
Yes. A magnitude 1.9 earthquake was recorded 3 km (2 mi) north-northwest of Aibonito, PR, at 5:06 pm AST on 18 October 2026 (21:06 UTC), 14 km deep. No felt reports to USGS yet.
USGS: 2 km NNW of Aibonito, Puerto Rico
35 km (22 mi) SW of San Juan, PR · 26 km (16 mi) WSW of Caguas, PR
- When
- 5:06 pm AST on 18 October 2026 ()
- Where
- 3 km (2 mi) north-northwest of Aibonito, PR · earthquakes near Aibonito
- Magnitude
- M 1.9 (md)
- Depth
- 14 km below the surface
- Felt
- no reports yet
- Nearest
- Aibonito Municipio, 4 km SSE
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 3 hours ago
Earthquake alerts for Aibonito, PR
Get a notification in this browser when USGS records an earthquake near Aibonito, PR. No account or email needed.
Alerts are on for .
Not a warning. An alert comes after USGS publishes a quake, usually minutes after the shaking. For early warning use ShakeAlert, through your phone's Wireless Emergency Alerts or the MyShake app.
This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.
At this magnitude and depth, people at rest would likely notice it out to about 4 km (2 mi) from the epicentre. In Aibonito, 3 km away, the estimate is intensity II (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.
Earthquakes near other towns within 30 km: Barranquitas, Pastos, Comerío, Parcelas La Milagrosa, Parcelas Nuevas, Vázquez.
How big was it?
This earthquake released about 21 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.9 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 730,000× the energy of this one
- Magna, Utah 2020 M 5.7 520,000× the energy of this one
- Around the size people start to feel M 3.0 46× the energy of this one
- This earthquake M 1.9 about 21 lb of TNT
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
The largest earthquake within 50 km since 2016 was M 5.0 on 2020-01-07 — about 46,000 times the energy of this one.
Before 2016, the USGS record lists 2 earthquakes of M5 or more within 50 km:
- 5.1 3 km W of Aguas Buenas, Puerto Rico · 19 km NE of this epicentre
- 5.0 3 km N of Brenas, Puerto Rico · 38 km N of this epicentre
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 18.1620, -66.2773. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Aibonito Municipio, PR | 4 km (2 mi) | SSE | earthquakes near Aibonito Municipio |
| Barranquitas Municipio, PR | 5 km (3 mi) | NW | earthquakes near Barranquitas Municipio |
| Comerío Municipio, PR | 9 km (6 mi) | NE | earthquakes near Comerío Municipio |
| Coamo Municipio, PR | 11 km (7 mi) | SW | earthquakes near Coamo Municipio |
| Cidra Municipio, PR | 12 km (8 mi) | E | earthquakes near Cidra Municipio |
| Naranjito Municipio, PR | 14 km (9 mi) | N | earthquakes near Naranjito Municipio |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
No further earthquakes have been recorded within 50 km since this one.
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
- The official USGS event page — the source of record for every value above
- Did you feel it? Report it to USGS — reports go to USGS, not to us
- ShakeMap for this event, when USGS has produced one
QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.