Earth Science chapter 8

6th grade-McDougal Littell Earth Science
An area of land that rises steeply from the land around it.
Long lines of mountains.
Mountain Belt
Ranges that are close together make up this.
Thick layers of __________ can build up in low-lying areas, such as valleys, lakes, or the ocean.
Folded mountain
A mountain that forms as continental crust crumples and bend into folds.
Fault-block mountains
Mountains that form as blocks of rock move up or down along normal faults.
An opening in Earth's crust through which molten rock, rock fragments, and hot gases erupt.
A major portion of all magma is ________.
When magma erupts, it is called _________.
Pyroclastic flow
A dense cloud of superhot gases and rock fragments that races downhill.
This collects in a chamber before erupting through a volcano.
Ash, cinders and block
_________,_________ and ________ are three types of rock fragment.
Volcanic bombs
The largest rock fragments.
Very hot and very fast
Two important characteristics of pyroclastic flow
Subduction Zones
___________, hot spots, and divergent boundaries are 3 specific places volcanoes form.
Shield Volcano
Shaped like a broad, flat dome and made of many thin layers of lava.
Cinder Cone
Steep, cone-shaped hill.Made of cinders and other rock fragments that pile up around a crater.
Composite Volcano
Steep at the top and flattens out near the bottom. It is built up of layers of lava and layers of rock fragments.
Huge craters formed by the collapse of a volcano when magma rapidly erupts from underneath it.
Earthquake activity
The tilt of the ground, temperatures at the opening, types of gases given off and __________________ are all ways scientists monitor volcanoes.
Are landslides that occur when loose rocks and soil are mixed with water.
Lava Flow
Slow-moving lava that will knock down, cover or burn nearly everything in its path.
Volcanic Ash
Tiny particles of rock that is heavy, can cover roadways, collapse roofs, and clog up machinery.
Rapid downhill movement of rock and soil.
Steam Explosion
Occurs when magma comes near water or into contact with it.
Acid Rain
Rain that contains large amounts of acid.
Hot Springs
Area where water moves down through the ground, gets heated, and rises where it flows out into a calm pool.
A type of hot spring where water shoots into the air.
Similar to a hot spring but instead of water, steam and other gases are released.
Deep Sea Vents
Hot sprigs that form at spreading centers in the ocean.
Bombs (or Blocks)
Large rock fragments that are thrown from a volcano that can be as large as a house.
Composite volcanoes have ___________ eruptions because of trapped gases and rising magma.
Mauna Loa
________________is a shield volcano and is one of Earth's most active volcanoes.
Silica content
The explosiveness of a volcanic eruption depends mostly on the ______________ of the magma.
World wide
Volcanic ash can be a _______________problem because the ash can be crried by the wind very far from the volcano.