M4.1 earthquake 45 km ENE of Tonopah, Nevada

A magnitude 4.1 earthquake struck 45 km ENE of Tonopah, Nevada on Wed, Apr 28, 2021, 4:57 AM PDT (11:57 UTC), 8 km (5 mi) below the surface.

A larger quake followed: M4.4 30 km SE of Mina, Nevada. This one was a foreshock.

Map

Where this earthquake was located, with the others nearby. Select one for its page.

Different scales measure different things and differ by a few tenths. The USGS marks one as preferred, and it is the one this page uses.

Mag.	Scale	Computed by	Notes
4.1	ML, local (Richter)	Nevada Seismological Laboratory	Preferred · Reviewed · ±0.33 · 10 stations
3.3	Mwr, regional moment	USGS National Earthquake Information Center	Reviewed · 9 stations
3.1	Mwr, regional moment	Nevada Seismological Laboratory	Moment tensor · Reviewed

The USGS ShakeMap: shaking estimated from seismic stations and the quake’s size, on the Modified Mercalli intensity scale.

1 person reported to the USGS what they felt; the strongest reported shaking was II, weak shaking.

How the rock slipped, from the moment tensor, and the USGS estimate of landslides and liquefaction.

Reviewed by a seismologist.

Distance and direction from each place to the epicenter, with its forecast.

Within 100 km, magnitude 1.5 and up: 121 in the 60 days after this one and 43 in the 30 days before it.

The first 60 of 121.

From the USGS Earthquake Hazards Program and its partner networks, event nn00806025 (also filed as us7000dy6v). Read Sat, Oct 3, 2026, 8:01 AM UTC.