Science Unit 4.2
If you see a very tall, rock feature that looks like a jagged, rectangular block sticking out of the ground, you're probably observing a _____.
Volcanic Neck
Which of the following statements are true?
Volcanoes can form mountains and islands. Volcanoes can form plateaus and lava domes. Geysers and hot springs occur due to hot, volcanic material inside the earth.
Batholith
a large mass of hardened igneous rock beneath all layers of sedimentary rock
Cinder Cone
a shorter peak made of ash and volcanic rock
Shield
a very tall and broad-sloped peak made of mostly lava flow
Composite
a very tall, steep-sloped peak made of both lava and volcanic materials
Guyout
a volcanic island under sea that has been cut off by wave erosion
Viscosity
ability of a substance to resist flowing
Hot Spot
an active area of volcanoes due to a consistent source of magma in the asthenosphere
Lahar
an avalanche of water, mud, and other materials that a volcanic eruption can produce
Strombolian Eruption
an intermittent explosive volcanic eruption
Seamount
an underwater volcano
How can a scientist predict how explosive the eruption of a volcano will likely be?
by studying the composition of its volcanic rock
Which of the following are warning signs that a volcano will soon erupt?
earthquakes or tremors, ground swelling, smoke plumes
Geothermal Energy
energy produced from the heat of magma and other volcanic materials
Which of the following are other natural hazards that can occur due to volcanic activity?
fires, tsunamis, earthquakes, landslides and mudslides, flooding
plume
gassy smoke released by a volcano
Sill
horizontal intrusion of magma between rock layers
Intrusive
igneous rock that forms in Earth's interior
Extrusive
igneous rock that forms on Earth's surface
tiltmeter
instrument used to measure ground swelling
correlation spectrometer
instrument used to measure volcanic gases
Laccolith
intrusive rock that pushes its way between sedimentary strata in the shape of a dome
Rhyolitic Magma
magma that has a high viscosity and high silica and gas content; eruption tends to be very explosive
Basaltic Magma
magma that has low viscosity and low silica and gas content; eruption is non-explosive
Andesitic Magma
magma that is a mix of basaltic and rhyolitic; eruption may or may not be explosive
Volcanic eruptions occur because of _____.
magma that needs to be released, plate tectonics, stress and pressure
Hawaiian Eruption
non-explosive or very mild volcanic eruption
Magma that squeezes into a horizontal crack is called a _____. Magma that squeezes into a vertical crack is called a _____.
sill, dike
Volcanic Neck
tall feature that forms when the sides of a volcano erode, leaving the rock that filled the central vent of the volcano
Plinian Eruption
the most powerful, explosive type of volcanic eruption
Dike
vertical intrusion of magma between rock layers
Pyroclastic Flow
volcanic flow that contains a high concentration of gases, ash, and small rocks
Tephra
volcanic rock and debris that is blasted from a volcano during an eruption
Cinder Cone Volcano
volcano formed of volcanic rock and ash; erodes quickly
Shield Volcano
volcano that has tall, broad slopes; formed by repeated, gradual lava flows
Composite Volcano
volcano that is tall and steep; formed of lava and volcanic debris
You can usually tell the difference between a caldera and crater by studying _____.
A feature's size and formation
What type of volcano would you most expect to erupt?
Active
Which of the following can be a result of a volcanic eruption?
Altering an area's climate, fires, tsunamis
The respiratory system of the body can be injured by volcanic _____ that comes from a volcanic eruption.
Ash
The type of lava least likely to form a pyroclastic flow is _____.
Basaltic
The Black Hills of South Dakota is an example of an eroded _____.
Batholith
Volcano is emitting gases.
COSPEC
Which type of volcano doesn't get very big or tall because it is susceptible to erosion?
Cinder Cone
What is one of the main problems with being able to predict when a volcanic eruption will occur?
Equipment and scientists' time is very expensive
Which of the following states was formed by continuous volcanic lava flow?
Hawaii
Basaltic
Hawaiian Eruption
Which intrusive feature may start as a sill but, as more magma builds, it pushes upward like a lens?
Laccolith
The three main parts of a volcano are _____.
Magma chamber, central vent, crater
The Ring of Fire is where many volcanoes occur because the _____ plate is subducted in nearly every region.
Pacific
Rhyolitic
Plinian Eruption
Choose the magma type which is most viscous:
Rhyolitic
Which type of magma is known for the most violent eruptions?
Rhyolitic
Small tremors are occurring.
Seismograph
Broad, gradual slopes are ___ volcanoes, while tall, steep slopes are ___ volcanoes.
Shield, composite
Andesitic
Strombolian Eruption
The ground by a volcano is moving upward.
Tiltmeter