volcanology

pyroclastic

Hot eruption debris

• ashfallAirborne volcanic debris descending
• calderaCollapsed volcanic summit basin
• fumaroleVolcanic gas vent
• laharVolcanic debris flow

tephra · pumice · vent · explosivity · scoria · effusive · explosive · crater

aa

Sharp, blocky lava flow

• lava tubeVolcanic drainage tunnel
• lava lakeMolten rock pool in crater
• lava flowMoving volcanic discharge
• basaltFine-grained volcanic stone

andesite · obsidian · viscosity · molten rock · lava dome · lava fountain · spatter · cooling rate

magma chamber

Subsurface pocket holding liquefied rock

• partial meltingIncomplete transition to liquid
• crystallizationForming ordered solid structure
• magmaticConcerning molten rock
• convectionHeat transfer via motion

basaltic · solidus · degassing · intrusion · dike · sill · pluton · mush

evacuation

Removal from danger

• disasterSudden ruinous event
• emergencySerious sudden danger
• toxic gasesHarmful airborne chemical substances
• pyroclastic flowHot volcanic gas-debris mixture

sulfur dioxide · acid rain · vog · exclusion zone · civil defense · risk assessment

subduction zone

Where one plate slides under another

• riftCrack or estrangement
• hotspotArea of notable activity
• plate boundaryWhere Earth's sections meet
• mid-ocean ridgeSubmarine volcanic mountain range

convergent · divergent · lithosphere · asthenosphere · Ring of Fire · oceanic crust

petrology

Scientific study of rocks

• mineralogyScience of inorganic solids
• geologyStudy of Earth's composition
• stratigraphyStudy of rock layers
• geochemistryEarth's chemical makeup science

geophysics · geochronology · fieldwork · thin section · tephrochronology

seismograph

Earthquake measuring device

• satellite imageryEarth views from orbit
• thermal imagingDetecting objects by warmth
• infrasoundSound below 20 Hz
• early warningAlert before event occurs

real-time monitoring