1.9
Earthquake Details: 3 km ENE of Portola Valley, California, United States
8/18/2026, 9:30:28 AM
A magnitude 1.9 earthquake occurred near 3 km ENE of Portola Valley, California, United States on 8/18/2026 at 9:30:28 AM. The seismic event was recorded at a depth of 5.82999992370605 km. No tsunami warning was issued.
No Tsunami WarningStatus: automaticType: earthquake
Regional Seismicity
Technical Details
Depth5.82999992370605 km
Significance59
Latitude37.3962
Longitude-122.2013
Event IDnc75420527
Magnitude1.9
Updated:8/18/2026, 12:27:22 PM
External Resources
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Time & depth
- Local time
- 8/18/2026, 2:30:28 AM PDT
- UTC
- 8/18/2026, 9:30:28 AM UTC
5.83 km · Shallow-focus
Less than 70 km deep. Shaking is often stronger near the epicentre.
Nearby major cities
Nearby event sequence · 12
M2.67 km SW of Atascadero, California, United StatesBeforeM2.810 km ENE of Coso Junction, California, United StatesBeforeM2.655 km W of Ferndale, California, United StatesBeforeM2.63 km SE of Concord, California, United StatesBeforeM2.712 km S of Lompoc, California, United StatesBeforeM3.249 km W of Petrolia, California, United StatesBeforeM2.57 km NW of Avenal, California, United StatesBeforeM2.735 km NNW of Santa Barbara Is., California, United StatesAfterM2.760 km W of Petrolia, California, United StatesAfterM2.628 km WNW of Weaverville, California, United StatesAfterM2.520 km ESE of Silver Springs, Nevada, United StatesAfterM2.511 km SW of Round Valley, California, United StatesAfter
Earthquake information is automatically aggregated from the official seismic agencies listed below. Preliminary measurements can change as agencies review an event; use local emergency authorities for safety decisions. Latest successful data update: Aug 18, 2026, 12:27 PM UTC.
Data sources:
- USGS — Credit: U.S. Geological Survey.
- EMSC — Credit: EMSC/CSEM. Event catalogue data are provided under CC BY 4.0. CC BY 4.0
- JMA — Source: Japan Meteorological Agency (JMA).
- Geoscience Australia — Based on Australian Earthquakes data by Geoscience Australia. © Commonwealth of Australia. Licensed under CC BY 4.0; the section 5 disclaimer applies. CC BY 4.0
- GeoNet — We acknowledge the New Zealand GeoNet programme and its sponsors NHC, Earth Sciences NZ, LINZ, NEMA and MBIE for providing earthquake data.