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Mt Lassen
Yes, it is an active volcano


What is that smell?


The Sulfur Works

As water from rain and melting snow seeps into the porous volcanic soils it becomes heated by contact with a mass of hot rocks that have been baked by this magma chamber. This water reaches temperatures of 465 degrees F. causing boiling with an increased pressure which forms a steam and gas reservoir over the hot water. This intense pressure causes the super-heated (above the boiling point) water to rise back towards the surface as steam, boiling water, super-heated fumaroles, acid-sulfate hot springs, and bubbling mudpots. These thermal pools can reach temperatures of 240 degrees F. at the surface.

You will catch the smell of rotten eggs in the air which is hydrogen sulfide, one of the volcanic gases released by the magma below.



John's favorite type of road