Increased seismicity, alerts raised for Pavlof volcano, Alaska
Seismic activity at Pavlof volcano, Alaska has increased over the past several days, forcing the Alaska Volcano Observatory to raise the Alert Level to Advisory and the Aviation Color Code to Yellow at 20:43 UTC on December 28, 2019. Pavlof is a snow- and ice-covered stratovolcano about 953 km (592 miles) southwest of Anchorage. With over 40 historic eruptions, it is one of the most consistently active volcanoes in the Aleutian arc. Pavlof's largest known historical eruption took place in 1911.
There is currently no observed eruptive activity or emissions from the summit.
Although the current seismic activity represents an increase from background levels, it does not necessarily mean that an eruption is likely or imminent. However, past eruptions of Pavlof occurred with little or no warning.
Small explosion signals have been detected on the infrasound network located at Sand Point and on the local seismic network on October 19, 2019.
It is unknown if the explosions produced any volcanic ash, but their small size suggests any hazard was confined to the area around the volcano's summit.
Low-frequency seismic tremor and vigorous steam plume have been observed on May 14 and 15, 2019.
Its last known eruption took place from March 27 to July 30, 2016 (VEI 2).
The most active volcano of the Aleutian arc, Pavlof is a 2 519-m-high (8 264 feet) Holocene stratovolcano that was constructed along a line of vents extending NE from the Emmons Lake caldera.
Pavlof and its twin volcano to the NE, 2 142-m-high (7 027 feet) Pavlof Sister, form a dramatic pair of symmetrical, glacier-covered stratovolcanoes that tower above Pavlof and Volcano bays.
A third cone, Little Pavlof, is a smaller volcano on the SW flank of Pavlof volcano, near the rim of Emmons Lake caldera.
Unlike Pavlof Sister, Pavlof has been frequently active in historical time, typically producing Strombolian to Vulcanian explosive eruptions from the summit vents and occasional lava flows. The active vents lie near the summit on the north and east sides.
The largest historical eruption took place in 1911, at the end of a 5-year-long eruptive episode, when a fissure opened on the N flank, ejecting large blocks and issuing lava flows. (GVP)
Featured image: AVO/USGS, Chris Waythomas
If you value what we do here, create your ad-free account and support our journalism.
Your support makes a difference
Dear valued reader,
We hope that our website has been a valuable resource for you.
The reality is that it takes a lot of time, effort, and resources to maintain and grow this website. We rely on the support of readers like you to keep providing high-quality content.
If you have found our website to be helpful, please consider making a contribution to help us continue to bring you the information you need. Your support means the world to us and helps us to keep doing what we love.
Support us by choosing your support level – Silver, Gold or Platinum. Other support options include Patreon pledges and sending us a one-off payment using PayPal.
Thank you for your consideration. Your support is greatly appreciated.
Commenting rules and guidelines
We value the thoughts and opinions of our readers and welcome healthy discussions on our website. In order to maintain a respectful and positive community, we ask that all commenters follow these rules:
We reserve the right to remove any comments that violate these rules. By commenting on our website, you agree to abide by these guidelines. Thank you for helping to create a positive and welcoming environment for all.