M5.7 Earthquake Swarm
Strikes Near Reno
A magnitude 5.7 mainshock hit Silver Springs, Nevada at 23:22 UTC on April 12, followed by 46 aftershocks in the hours since. The sequence is centered in the Walker Lane seismic zone, one of the most active fault systems in the western United States.
Epicenter Map
Interactive map showing all 47 events. Circle size scales with magnitude. Red = M5+, orange = M3+. Data: USGS FDSN Event Web Service.
What Happened
At 23:22 UTC on April 12, 2026, a magnitude 5.7 earthquake struck approximately 20 km east-southeast of Silver Springs, Nevada — roughly 50 km east of downtown Reno. The shallow depth (5 km) means the shaking was strongly felt across the Reno-Sparks metropolitan area (population approximately 500,000) and surrounding communities.
Within 30 minutes of the mainshock, 25 aftershocks of magnitude 2.0 or greater were recorded by the USGS seismic network. As of this writing, the total stands at 47 events above M1.5, with 9 reaching M3.0 or above. The largest aftershock so far is M3.6.
The Walker Lane
The sequence is centered in the Walker Lane seismic zone, a 100-km-wide belt of active faults running from the Mojave Desert to northern Nevada. The Walker Lane accommodates approximately 20% of the Pacific-North American plate boundary motion that doesn't occur on the San Andreas fault, producing frequent moderate earthquakes and occasional large ones.
The Reno area has experienced notable seismic sequences before. The 2008 Mogul swarm produced thousands of small earthquakes over several months, peaking at M4.7. Today's M5.7 is significantly larger — the strongest in the immediate Reno vicinity in decades.
Sequence Timeline
The foreshock activity beginning approximately 75 minutes before the mainshock is notable. Foreshock sequences precede roughly 5–10% of moderate mainshocks, but are not reliably predictive in real time.
Context: A Seismically Active Week
This is the second significant earthquake swarm in the western US this week. On April 10, a swarm of 23 events was recorded off the Washington coast near the Juan de Fuca Ridge (max M4.2). Some social media accounts incorrectly linked that swarm to the Cascadia Subduction Zone — the events were actually on the mid-ocean spreading center, approximately 400 km west of the subduction trench.
Today's Nevada sequence is unrelated to the offshore Washington swarm. The Walker Lane and the Juan de Fuca Ridge are independent fault systems separated by over 1,000 km.
What to Expect
Following a M5.7 mainshock, USGS aftershock forecasts typically project a 5–10% chance of a larger earthquake (M6+) in the coming days, and near-certainty of continued M3+ aftershocks for weeks. Aftershock sequences in the Basin and Range typically decay over 1–3 months.
TerraPulse is monitoring this sequence in real time through our USGS earthquake data feed. This page will be updated as significant aftershocks occur.
Data: USGS FDSN Event Web Service. Map generated from GeoJSON query: lat 38.5–40.5, lon -120.5 to -119.0, M1.5+. All times UTC. Updated April 13, 2026.