A quiet eruption produces what type of dangerous hazard?

Where do most volcanoes form?

The Hawaiian islands are formed by

Volcanoes that have both lava flows and pyroclastic flows are called

The opening of a volcano labeled "A" is called what?

The connecting pipe between the magma chamber and the vent labeled "C" is called what?

The place where all the lava comes from labeled "D" is called the?

The location where a volcano erupts but it is not its main exiting point labeled "F" is called

A huge crater caused by the collapsing of a magma chamber is called a _______.

A large, flat volcano that produces quiet eruptions is called a

Nonviscous lava that is very runny but very hot is called

Viscous Lava that produces slowly moving blocks because it has a lot of silica is called

A stratovolcano is also known as a _______.

A volcano that produces large pyroclastic flows only is called a

A large cloud of hot ash, cinders, blocks, etc. that travels very fast is called

Viscosity of magma is determined by

If the silica in the magma goes up, then the viscosity of the magma goes

If the viscosity of magma goes up, then the eruption is

This gas is responsible for the rotten egg smell that you smell around volcanoes and hot springs.

What volcanic feature happens when magma cuts through rock vertically?

What volcanic feature happens when magma cuts across sedimentary rock horizontally?

What type of volcano is shown above?

Openings in the Earth's crust through which molten rock flows to the surface, usually forming mountains, are called __________.

The major belt of volcanoes and tectonic activity that surrounds much of the Pacific Ocean:

What is molten rock that has reached the Earth's surface called?

What factor(s) determine(s) whether an eruption will be explosive?

Vocanoes are found...

A live volcano is called a/an:

What type of volcano has large, fairly steep slopes made of alternating layers of ash and silica rich lava?

This city was destroyed in 79 A.D. by the eruption of Mt. Vesuvius.

Rank the volcanic stages from LEAST likely to MOST likely to erupt.

What tool helps a volocanologist to monitor seismic activity?

Lava that is very thin and runny, or has low viscosity, probably

A bowl shaped area that may form at the top of a volcano around the central vent

Volcanoes form in different ways and release different types of lava. There are two main types of volcanoes. Shield volcanoes form when thin, runny lava is released. This magma does not contain a lot of gas, so it has less energy. Because of this, it releases relatively gently and lava flows far down the sides of the volcano before cooling. Shield volcanoes are wide and flat, resembling a shield of armor. Composite volcanoes are formed by magma that contains a lot of gas. The thick magma builds up an enormous amount of pressure, causing an explosive eruption. Lava from a composite volcano cools quickly and doesn’t flow very far. As a result, lava piles up and creates mountainous slopes. A composite volcano is most likely what you imagine when you think of a volcano.

Which of the following best describes the relationship between gas and volcanic eruptions?

Volcanoes usually occur at fault lines. Fault lines are where tectonic plates push together, pull apart and slide past each other. The energy created here forms volcanoes and causes eruptions. This isn’t the only way volcanoes form though. Some volcanoes, like those found in Hawaii, occur over hot spots. Hot spots are portions of the mantle at which the temperature is abnormally high. These high temperatures cause magma to rise and break through Earth’s crust. This type of volcano often forms a seamount. A seamount is an undersea mountain that becomes an island if it surpasses sea level. While a seamount is over a hot spot, it remains volcanically active. But over the course of millions of years, as tectonic plates shift and the seamount moves, the volcano eventually becomes extinct.

When is a seamount volcanically active?

Volcanoes can be categorized as active, dormant or extinct. Although definitions vary from scientist to scientist, a volcano is considered active if it has erupted recently or erupts regularly. A dormant volcano refers to a volcano that has not erupted recently, but will likely erupt again. An extinct volcano is a volcano that will never erupt again because its magma supply has been cut off. One point of disagreement between scientists is their definition of “recently.” For some, it means within the last 10,000 years. For others, much shorter. The line between active, dormant and extinct volcanoes can be blurry. In some rare cases, volcanoes long thought to be extinct have unexpectedly come back to “life.”

Which of the following would most likely be classified as an active volcano?

Volcanic eruptions can happen quickly. When an eruption occurs, there isn’t much that can be done to slow its destructive force. Because of this, scientists are continuously working to improve their ability to predict eruptions. Better technology means evacuation warnings can be issued before it’s too late. Earthquakes caused by magma pushing up through the volcano are one indicator of an approaching eruption. Vibrations from these earthquakes can be detected by a device called a seismometer. Another sign a volcano may soon erupt is swelling of the volcano itself. As magma builds up, the magma chamber enlarges and changes the shape of the volcano. These changes can be identified by tilt meters, devices that measure the tilt of a structure. Gas release can also signal an eruption. Although changes in the atmosphere around a volcano tend to be small, scientists have developed devices to detect these minor changes. Predicting eruptions is all about safety. The sooner these indicators can be identified, the more time those who live near volcanoes will have to evacuate.

With which of the following statements would the author of this passage most likely agree?

What type of volcano is this?

Repeated floods of molten material can form high, level plateaus called...

The destructive mudflow on the slopes of a volcano is called :

An instrument that simply detects earth waves is a ________________.

Subduction would most likely be occurring at a ____________ boundary.

What is a major difference between a fault and a joint?

The horizontal direction of a fault is its ___________.

The angle that the face of a fault makes with the horizontal is its _________.

Most major faults in the United States are found in ________________.

What is the name of the longest strike-slip fault in southern California?

Rayleigh waves and Love waves are both examples of ___________.

Which of the following in not related to locating an earthquake?

Earthquakes are most common

One quake measures 6.0 on the Richter scale and another measures 7.0. How does the second quake's energy compare with that of the first?

An impending earthquake

An ocean wave caused by an earthquake is called a(n) _____________.

Waves that do not travel through the earth's interior

Last waves to arrive at a seismic station

Second waves to arrive at a seismic station

Most destructive earth waves

Strongest and slowest body waves

First waves to arrive at a seismic station

Not required to determine an earthquake's epicenter

Love and Rayleigh waves

Indicates the energy released during an earthquake

Earthquake hazard, especially in urban areas

Earthquake hazard, especially in mountainous areas

Identifies the destructiveness of an earthquake

Earthquake hazard, especially in coastal areas