What is a Volcano?
Magma that reaches the earth's surface
What is lava?
A rapid downhill movement of hot, solid, volcanic particles suspended in steam; more deaths occur because of this than from flowing lava
What is a pyroclastic flow or glowing avalanche?
Most active volcanoes in the world exist near this type of tectonic plate boundary
What are convergent tectonic plate boundaries?
Volcanoes are classified by structure, explosivity, and this
What is activity?
A volcano having no historical record of eruption and showing no seismic indications of activity
What is an extinct volcano?
A spring that periodically ejects large quantities of hot water (heated by magma) and steam
What is a geyser?
The depression found at the top of a volcano
What is a crater?
Tiny, angular, glassy fragments
What is ash?
This volcano belt is also known as the Ring of Fire
What is the Circum-Pacific volcano belt?
The typical young-earth geologist believes that volcanoes formed during or shortly after this event
What is the Flood?
A volcano that has not erupted in historical times but is not significantly eroded (according to USGS)
What is a dormant volcano?
The internal energy of the earth that is sometimes harnessed for man's use
What is geothermal energy?
The type of rock that makes up volcanoes
What is igneous rock?
A layer of loose pyroclastic materials and ash covering the ground
What is tephra?
Wall-like igneous intrusions
What are dikes?
The volcano type that takes up the most land area, it emits mostly lava in quiet eruptions
What is a shield volcano?
The most common volcanic structure, it emits lava and solid debris in alternately quiet and explosive eruptions
What is a stratovolcano?
Batholits and laccoliths are types of these
What are plutons?
Viscous lava contains more of this than runny lava does
What is silica?
Streamlined mass of ejected lava that has solidified in flight
What is a bomb?
Mineral terraces are often associated with these
What are hot springs?
Young-earth geologists would consider what kinds of volcanoes active based on a biblical view of Earth's history
What are all three (active, dormant, extinct)?
A volcano that emits mostly cinders, ashes, and bombs
What is a cinder cone?
The geothermal gradient is highest here
Where is the lithosphere?
An enlarged depression that is caused by an explosion or the collapse of a volcanic cone
What is a caldera?
A mudslide caused by a volcano
What is a lahar?
Thick layers of igneous rock covering large portions of the earth thought to have formed when huge quantities of magma were released through cracks in the earth's crust
What are flood basalts or basalt traps?
The largest volcanic eruptions in the history of the earth were probably similar to this
What is the eruption that formed the Yellowstone Caldera?
The scale that geologists use to classify the destructiveness of a volcanic eruption, using the amount of tephra a volcano produces, the height of the eruption cloud, and a descriptive estimate of the explosion
What is the Volcanic Explosivity Index (or VEI)?
Secular geologists believe that most of the earth's internal heat comes from this
What is radioactive decay?