lava dome
Magma plug formation
A lava dome is a mound of viscous lava that accumulates around a volcanic vent rather than flowing away.
The thick, slow-moving lava piles up in a rounded mass, sometimes within a crater.
Lava domes can grow over months or years and may collapse suddenly, triggering pyroclastic flows: The volcano's lava dome had been building for weeks before it exploded.
Pale volcanic igneous rock
- andesiteIntermediate volcanic rock
- obsidianGlassy igneous rock
- pumiceLightweight volcanic abrasive
- crystallizationForming ordered solid structure
groundmass · glass · vesicular
Pushing through a die
- viscousThick and slow-flowing
- silica-richHigh silicon dioxide content
- spineColumn of vertebrae
- couleeSeasonal streambed carved deep
growth · collapse · endogenous · exogenous · lobe · solidification · carapace · talus
Layered cone-shaped volcanic mountain
- calderaCollapsed volcanic summit basin
- craterImpact or volcanic basin
- ventOpening for airflow
- fumaroleVolcanic gas vent
geothermal · hydrothermal · magma chamber · conduit · volcanology · monitoring · seismicity · deformation
rhyolite
Pale volcanic igneous rock
extrusion
Pushing through a die
- viscousThick and slow-flowing
- silica-richHigh silicon dioxide content
- spineColumn of vertebrae
coulee · growth · collapse · endogenous · exogenous · lobe · solidification · carapace · talus · effusion
stratovolcano
Layered cone-shaped volcanic mountain
fumarole · geothermal · hydrothermal · magma chamber · conduit · volcanology · monitoring · seismicity · deformation · degassing
pyroclastic
Hot eruption debris
tephra · ashfall · rockfall · instability
Mount St. Helens
Active Washington stratovolcano
- geologybedrock, fault lines, faults, rock, basalt
- landformsmountain, cliff, valley, volcano, mountain ridge
- volcanic activityeruption, active, dormant, magma, extinct
- volcanoesvolcano, volcanic eruption, Mount Fuji, volcanic eruptions, caldera
- volcanic sitesvolcano, crater, caldera, geyser, fumarole
- volcanicmagma, tephra, pumice, scoria, ash fall