Public Summary — February 3, 2026 What We Know About Recent Seismic “Booms” in Washington State Today, the U.S. Geological Survey (USGS) officially reported that several recent seismic events across Washington State were not traditional earthquakes. Instead, they were classified as “explosions”, based on how the ground motion looked on seismic instruments and how shallow the events were. This classification does not mean bombs or attacks. In scientific terms, “explosion” simply means the shaking