They shoot molten lava and toxic gases miles into the atmosphere and when the lava is too thick to run over the top, it can create what geologists like Dr. Pat Abbott call a plug dome volcano.

The park is home to more than 40 volcanoes, bubbling mudpots, steaming fumaroles, stunning mountain views and vast, naturally dark skies. The park's namesake peak is the one of the largest plug dome ...

The park is home to more than 40 volcanoes, bubbling mudpots, steaming fumaroles, stunning mountain views and vast, naturally dark skies. The park's namesake peak is the one of the largest plug dome ...

Four types of volcanoes—shield, composite, cinder cone, and plug dome—can be found in Lassen Volcanic National Park, where they literally bubble and steam.

Lassen Volcanic National Park is home to all four kinds of volcanoes found on Earth, including one of the largest plug-dome volcanoes: Lassen Peak (10,457 feet). Most of the park is closed in ...