explosion · reviewed by a seismologist
M 1.5ml
Earthquake near Tillamook, OR
USGS: 22 km ENE of Tillamook, Oregon
72 km (45 mi) W of Portland, OR · 49 km (31 mi) W of Hillsboro, OR
- When
- 12:51 pm PDT on 8 October 2018 ()
- Where
- 23 km (14 mi) ENE of Tillamook, OR · earthquakes near Tillamook
- Magnitude
- M 1.5 (ml)
- Depth
- -0.3 km below the surface
- Felt
- no reports yet
- Nearest
- Tillamook County, 17 km WSW
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 559 days ago
A magnitude 1.5 earthquake was recorded 23 km (14 mi) ENE of Tillamook, OR, at 12:51 pm PDT on 8 October 2018 (19:51 UTC). This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.
Earthquakes near other towns within 30 km: Bay City.
USGS catalogues this as explosion, not an earthquake.
How big was it?
This earthquake released about 5.7 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.5 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 2,600,000× the energy of this one
- Magna, Utah 2020 M 5.7 1,900,000× the energy of this one
- Around the size people start to feel M 3.0 170× the energy of this one
- This earthquake M 1.5 about 5.7 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
No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.
Before 2016, the USGS record since 1900 lists no earthquake of M5 or more within 50 km.
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 45.5240, -123.5698. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Tillamook County, OR | 17 km (10 mi) | WSW | earthquakes near Tillamook County |
| Yamhill County, OR | 37 km (23 mi) | SSE | earthquakes near Yamhill County |
| Washington County, OR | 37 km (23 mi) | E | earthquakes near Washington County |
| Clatsop County, OR | 57 km (35 mi) | N | earthquakes near Clatsop County |
| Columbia County, OR | 60 km (37 mi) | NE | earthquakes near Columbia County |
| Polk County, OR | 71 km (44 mi) | S | earthquakes near Polk County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
41 earthquakes have been recorded within 50 km since this one.
- 1.6 17 km WNW of Banks, Oregon
- 1.5 5 km ENE of Sheridan, Oregon
- 1.7 4 km NE of Lafayette, Oregon
- 1.5 7 km WNW of Forest Grove, Oregon
- 2.0 4 km WSW of Wheeler, Oregon
- 1.5 8 km W of Yamhill, Oregon
- 1.6 9 km NNE of Sheridan, Oregon
- 1.9 10 km NNE of Sheridan, Oregon
- 1.7 13 km N of Willamina, Oregon
- 2.4 10 km N of Sheridan, Oregon
- 1.6 3 km WNW of Lafayette, Oregon
- 1.8 1 km NNW of Dayton, Oregon
- 1.7 11 km WNW of Beaver, Oregon
- 1.8 4 km NE of Lafayette, Oregon
- 1.6 10 km SW of Vernonia, Oregon
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.