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Pacific Mountain System

Lassen Peak

Lassen Peak

Lassen Volcanic National Park

Photo by M. Moreno, USGS.

Mount Lassen is the southern most of the Cascades Volcanoes. It last erupted in 1914-17.

Click here to learn more.

Bumpass Hell mud pots

Bumpass Hell

Lassen Volcanic National Park

Photo by M. Moreno, USGS.

Escaping gasses, heated by hot volcanic rock beneath the surface, bubble out of Bumpass Hell's mudpots.

Bumpass Hell mud pots

Bumpass Hell

Lassen Volcanic National Park

Photo by M. Moreno, USGS.

Escaping gasses bubble out of Bumpass Hell's mudpots.

Bumpass Hell mud pots

Bumpass Hell

Lassen Volcanic National Park

Photo by M. Moreno, USGS.

Steam rises from fractures and sulfur-rich pools at Bumpass Hell.


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This site is a cooperative endeavor of the
US Geological Survey Western Earth Surface Processes Team
and the National Park Service.

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http://geology.wr.usgs.gov/docs/usgsnps/province/lavo.html
This page was last updated on 10/10/00