Swarm of 100-plus small quakes rumble beneath Mount Hood

Not unusual, geologists say

GOVERNMENT CAMP, Ore. (KTVZ) — A swarm of more than 100 small earthquakes shook the south side of Mount Hood Sunday afternoon.

The strongest, a magnitude 2.7, occurred at 3:38 p.m., KGW reported.

Swarms of small magnitude quakes are not uncommon among the Cascade volcanic peaks. The activity can last hours, sometimes days.

"The earthquakes are associated with regional faulting and are not a sign of changes in volcanic activity," the U.S. Geological Survey said in a statement Sunday.

The USGS noted Sunday's swarm occurred in a location similar to a handful of other notable swarms in the last decade.

Just last fall, the USGS Cascade Volcano Observatory installed three new monitoring stations on Mt. Hood. The three stations improved a seismic, GPS and volcanic gas monitoring network already functioning at the mountain.