Overview
- USGS records show a 4.4-magnitude quake near Groom Lake on Wednesday at about 4 kilometers depth, followed by roughly 16 smaller events over the next one to two days.
- More than 100 people told USGS they felt the shaking, and officials reported no damage with intensity consistent with weak shaking.
- USGS geologist Christopher DuRoss said the depths match typical earthquakes, called it a mainshockâaftershock sequence rather than a swarm, and linked it to Basin-and-Range faulting.
- Geophysicist Stefan Burns said the signals are most likely tectonic yet noted some ambiguity, a nuance that has fueled online claims of covert tests without evidence.
- An active USGS forecast estimates a 54% chance of a magnitude 3 or stronger aftershock through May 7, with 10% for a magnitude 4 and 1% for a magnitude 5, as monitoring continues.