Magma
A 3-phase mixture composed of liquid (with O, Si, etc.), crystals (with O, Si, etc.), and gas bubbles (O, H, C, S)
What is magma?
Small, monogenetic, and mafic volcanic landform commonly found on the flanks of larger volcanoes
What is a cinder cone?
Volcanic hazard that damages infrastructure, rarely kills, and follows the landscape’s topography
What are lava flows?
The three main signs of volcanic unrest
What are seismicity, ground deformation, and gas emission?
Second layer of the atmosphere from 10-55 km altitude, with stable air flow from equator to poles
What is the stratosphere?
Process causing rock to partially melt as it moves from great depths to shallower depths
What is decompression melting?
Large, mafic volcanic landform characterized by gentle slopes and often forming intraplate ocean islands
What are shield volcanoes?
Rock fragments and particles of any size ejected by a volcanic eruption
What is tephra?
The single most crucial volcano monitoring tool measuring ground vibration
What is a seismometer?
Volcanic gas causing global cooling if injected in the stratosphere
What is sulfur dioxide (SO2)?
Resistance to flow of a fluid and key property influencing magma behavior
What is viscosity?
Mildly explosive eruption producing intermittent mafic lava fountaining blasts
Factors controlling dispersal of volcanic ash
What are eruption column height and wind?
Probabilistic assessment of future volcano behavior based on geologic record of past eruptions
What is long-term eruption forecasting?
Natural temporal records of past sulfur-producing eruptions
What are polar ice sheets?
Process that changes magma composition and can trigger volcanic eruptions
What is magma mixing?
Highly explosive eruption producing a sustained ash- and gas-rich column reaching the stratosphere
What is a Plinian eruption?
Lethal volcanic hazard caused by the collapse of an eruption column or lava dome
What is a pyroclastic flow?
Probabilistic assessment of volcanic activity based on volcano monitoring data
What is short-term eruption forecasting?
Natural temporal records of cooling due to past eruptions
What are tree rings?
Process by which crystallizing minerals cause a change in magma composition
What is fractional crystallization?
Three key factors controlling the style of volcanic eruptions
What are magma viscosity, gas content, and ascent rate?
The three main gases emitted from volcanoes
What are H2O vapor, CO2 and SO2?
Effective volcanic hazard mitigation measures
What are alert levels, preparedness, and coordinated emergency procedures
Effects of massive CO2 emissions during flood basalt volcanism (large igneous provinces)
What are global warming and mass extinctions?