A fork in the rock
What is the process of magma rising through layers of rock called?
Intrusion
What benefit of volcanoes is most useful for farmers/agriculture?
Soil rejuvenation (nutrients)
This sign that a volcano might erupt can be measured on a seismometer.
Increase in number of earthquakes
What type of volcanic rock has the least silica in it?
Basalt
What electrical phenomenon can be caused by a volcanic eruption?
Lightning
Magma that intrudes and cools across several layers is called what?
Dike
What benefit of volcanoes would provide electricity for your house?
Geothermal energy
What change in the surface of a volcano could mean that the volcano might erupt?
Inflation
What type of volcanic rock has the least iron and magnesium in it?
Rhyolite
When ash from a volcano mixes with water in a cloud what weather pattern occurs?
Magma that cools between two layers is called what?
Sill
What benefit of volcanoes is most appreciated by real estate agents?
Location, location, location
What sign that a volcano might erupt soon can you smell?
Increased emission of volcanic gases
A rock rich in silica is described as what?
Felsic
What product of explosive eruptions can warm the Earth?
Volcanic gases such as carbon dioxide
What is the pool of magma at the bottom of a volcano called?
Magma chamber
What benefit of volcanoes helps us build roads and countertops?
Resources or building materials
When a magma chamber empties as the result of a volcanic eruption, what process occurs on the volcano?
Deflation
What is the process that melts rock when it rises inside the Earth?
Decrease in pressure
What product of explosive eruptions can cool the Earth?
Ash
The depression at the top of a volcano has this name.
Crater
What term is used to describe the formation of our atmosphere by volcanoes?
Outgassing
What formation is created by inflation and sudden deflation of a magma chamber?
Caldera
What is the most common way that melt is formed at subduction zones?
Addition of water
What part of the atmosphere must an eruption column enter to have a global effect?
Stratosphere