A volcano is a vent or fissure in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. [1]

Mar 26, 2026 · Volcano, vent in the crust of Earth or another planet or satellite, from which issue eruptions of molten rock, hot rock fragments, and hot gases. The term volcano can also refer to the …

USGS scientists monitor over 160 active and potentially active volcanoes in the United States. Some of these are erupting now and others could erupt at some point in the future. Most of these volcanoes …

May 21, 2025 · A volcano is an opening in a planet or moon’s crust through which molten rock and gases trapped under the surface erupt, often forming a hill or mountain.

Jul 10, 2025 · Volcanoes are Earth’s geologic architects. They’ve created more than 80 percent of our planet’s surface, laying the foundation that has allowed life to thrive. Their explosive force crafts...

Apr 17, 2023 · Volcanoes both build and destroy landscapes. Eruptions of lava, ash, volcanic bombs, blocks, and cinders form new land on oceanic islands, and build towering and inspiring snow …

2 days ago · The PVMBG volcano observatory reported a seismic signal with a maximum amplitude of 22 mm and a duration of 52.13 seconds. In order to mitigate risk, people are advised to avoid the …

The Smithsonian / USGS Weekly Volcanic Activity Report (WVAR) for the week ending on 22 April 2026 includes the 27 volcanoes shown below marked "Yes" in the WVAR column (rollover for report). The …

From lava fountains to towering ash clouds, volcanoes produce some of the most dramatic geological events on the planet. Volcanoes are cracks in Earth's crust that allow molten rock and hot...

Mar 20, 2026 · Volcano Observatory staff monitor, research, and issue formal notices of activity for volcanoes in assigned geographic areas. Scientists also assess volcano hazards and work with …