tephra
Airborne eruption fragments
Tephra is volcanic material ejected during an eruption—ash, rock fragments, and pumice that fall back to earth.
The term covers everything from fine dust to large boulders, classified by size: ash is smallest, then lapilli, then volcanic bombs.
Layers of tephra help geologists date ancient eruptions.
Lightweight volcanic abrasive
- scoriaPorous volcanic ejecta
- ashCombustion's powdery remains
- cinderCombustion residue fragment
- volcanic bombsEjected molten rock masses
obsidian · basalt · andesite · rhyolite · tuff · breccia · agglomerate · crystals
Hot volcanic gas-debris mixture
- explosionViolent burst of energy
- plumeOrnamental feather or rising column
- falloutPost-blast atmospheric particles
- airfallDebris settling from atmosphere
blast · vent · fissure · crater · caldera · lahar · surge · ashfall
Airborne volcanic debris descending
- respiratoryRelated to breathing organs
- aviationFlying or operating aircraft
- crop damageHarm to cultivated plants
- roof collapseStructure's top falling inward
water contamination · visibility · abrasion · lahars · mudflows · burial · evacuation · exclusion zone
Study of erupting mountains
- stratigraphyStudy of rock layers
- geochronologyStudy of geological ages
- geochemistryEarth's chemical makeup science
- petrologyScientific study of rocks
radiocarbon dating · paleomagnetism · thermoluminescence · correlation · fingerprinting · proxy · paleoclimate · archaeology
Single thickness of material
- stratumHorizontal layer of material
- bedFurniture for slumber
- sedimentParticles settling in liquid
- mantleCovering or wrap
blanket · loess · unconformity · welded · unwelded · cross-bedding · thickness · distribution
pumice
Lightweight volcanic abrasive
volcanic bombs · obsidian · basalt · andesite · rhyolite · tuff · breccia · agglomerate · crystals · xenoliths
pyroclastic flow
Hot volcanic gas-debris mixture
- explosionViolent burst of energy
- plumeOrnamental feather or rising column
- falloutPost-blast atmospheric particles
airfall · blast · vent · fissure · crater · caldera · lahar · surge · ashfall · ejecta
ashfall
Airborne volcanic debris descending
- respiratoryRelated to breathing organs
- aviationFlying or operating aircraft
- crop damageHarm to cultivated plants
roof collapse · water contamination · visibility · abrasion · lahars · mudflows · burial · evacuation · exclusion zone · air quality
volcanology
Study of erupting mountains
- stratigraphyStudy of rock layers
- geochronologyStudy of geological ages
- geochemistryEarth's chemical makeup science
petrology · radiocarbon dating · paleomagnetism · thermoluminescence · correlation · fingerprinting · proxy · paleoclimate · archaeology · ice cores
layer
Single thickness of material
mantle · blanket · loess · unconformity · welded · unwelded · cross-bedding · thickness · distribution · compaction