Particle.news

Download on the App Store

Mount Rainier Experiences Largest Earthquake Swarm Since 2009

Hydrothermal fluid circulation beneath the summit is driving the seismic swarm with the volcano’s alert level unchanged.

ASA lenticular cloud forms over Mount Rainier, considered an active volcano rising to 14,410 feet above sea level, as viewed from Reflection Lakes on August 29, 2024, near Ashford, Washington.
Mount Rainier, an active volcano rising to 14,410 feet, is experiencing a rare earthquake swarm.
Image

Overview

  • The swarm began on July 8 at 1:29 a.m. local time with hundreds of small quakes recorded at depths of 2–6 km and a maximum magnitude of 1.7.
  • It is the most significant earthquake cluster at Mount Rainier since a 2009 event that produced over 1,000 tremors in three days.
  • Scientists at the USGS Cascades Volcano Observatory and the Pacific Northwest Seismic Network attribute the quakes to hydrothermal fluid movements rather than magma intrusion.
  • No ground deformation, gas anomalies or surface-felt tremors have been detected and both the Volcano Alert Level and Aviation Color Code remain at green.
  • Annual swarms beneath the glacier-covered peak fit within its normal background activity and are monitored in real time by a dense network of seismic, infrasound, GPS and webcam stations.