2018 USGS National Volcanic Threat Assessment UPDATE

Alex Wierbinski's picture

By Alex Wierbinski - Posted on 26 October 2018


Mountain Safety & Understanding Our Terrain

2018 Update to the U.S. Geological Survey National Volcanic Threat Assessment,
USGS, October 22, 2018, PDF.

       USGS Abstract-Introduction Page

Information & Awareness
Western US Maps & the Threat List

The main point of this whole exercise is to make citizens and public safety officers aware of the nature and extent of potential local and regional volcanic threats.

This assessment information, along with some good news reporting, may have discouraged some of the folks backpacking Mount Saint Helens the day it blew...

Volcano Hazards Program

Earthquake Hazards Program

Today's Earthquake Map

My point here is that you are needing to be informed if there are swarms of earthquakes running around your favorite wilderness area, especially if the side of your favorite mountain is bulging-out... you should have know that before you departed...

Active Threats!
The recent growth of the Big Island and the explosion of Mount Saint Helens, still #2 on our currently updated risk list, reminds us that the West Coast and the Sierra Nevada are active parts of the, “Ring of Fire,” where shaking and fire are not uncommon, but expected.

Is it time to, "Rock & Roll," again?

Which reminds us we are crossing active terrain that’s always in motion, and that sometimes it moves very quickly…

California Threat Map, p.14 of the Assessment
2018 map of volcanic threats in California.

NOTE: Use "View Image" in your browser to see the full sized image
(As with all the killer images on this site...)

USGS California Volcano Observatory (CalVO)

Our goal here is to give you an easy resource to identify the potential for volcanic, and by extension, temblor activity. These maps clearly lay out the most risky points, for us backpackers in California and the Sierra, (plus Alaska, Hawaii, and the Pac Northwest...) while the list below the maps quantifies these risks more precisely.

Western US, Canada, & Alaska Volcanic Threat Map, p.3 of Assessment
USGS 2018 Western US, Canada, & Alaska volcanic threats.

USGS Cascades Volcano Observatory (CVO)


We can see our volcanic threats are fairly constrained in California, then increase significantly as we travel further North into Washington, and go crazy out the Aleutian Range and it island-chain peninsula

Alaska Volcanic Threat Map, p.18 of Assessment
USGS 2018 Alaska Volcanic Threat Map.

Alaska Volcano Observatory (AVO)


Even before Alaska, we've got to look towards the ever-growing South end of the Hawaiian Islands for constant volcanic activity, growing new island as the ancient lushness of the northernmost ends of the islands falls into the sea...

Hawaii Volcanic Threat Map, p.23 of Volcanic Threat Assessment USGS 2018 volcanic threat assessment Hawaii Threat Map.


USGS Hawaiian Volcano Observatory (HVO)


Let's check out the Top US Volcanic Threats

USGS List of top forty-one US volcanic threats during 2018.


Volcanic Threats
California and the High Sierra

USGS California Volcano Observatory (CalVO)

Here in California we have three Volcanos in the Red, the "Very High Threat" catagory, with the Long Valley Caldera on the West Flank of the Sierra in the top twenty.


Shasta at #5

Lassen at #11

Long Valley at #18


The Local Threat

Long Valley Caldera

Geology News: Ancient High Sierra Geology, Long Valley on the East Flank


Supplemental Report

Long Valley & Mammoth Responds


Are we all going to die? Probably not from a volcano, says Dr. Nathan Andersen,
The Sheet, November 11, 2017, p.1, PDF.

Top: Original Research Article


Resources & References

Long Valley Caldera

Long Valley Caldera Map

Basic High Sierra Geological Resources



Volcanic Threats, #41-84, p. 9 of USGS 2018 Threat Assessment

US Volcanic Threats Chart, 41 through 84.


Volcanic Threats, #8-1274, p. 10 of USGS 2018 Threat Assessment

 There is one more page of potential, "green-level," of low level volcanic threats in the US, that can be seen on the report, along with a whole bunch more information and details. These are the main resources for us High Sierra backpackers...





All Geology News





October 2018 News of Man & Nature





News from Nature


Climate Destruction News



Bee News

Bear News

Spider Forum

Bird News

Small Mammals

Frogs and Reptiles

Butterfly News


Health and Fitness

Mountain Safety

Mosquito News

Female Trail

High Sierra History


Astro-Phys, Space, & Science News

High Sierra Geology News

Fish, Oceans, & Water News



All High Sierra News





 2018 USGS United States Volcanic Threat Assessment


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