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63 Cards in this Set

  • Front
  • Back
What famous cinder volcano exists in Mexico?
Volcanic eruption characterized by an outpouring of lava with a lack of explosive activity:
Effusive eruption
Which lava compositions have a high amount of silica?
Intermediate, felsic (thick /sticky…cool lava)
What is Devil’s Tower known for?
Its famous columnar joints
A low and fairly rounded volcano that is produced by effusive eruptions:
Shield volcano (ex: Hawaiian volcanoes, Mauna Loa in Hawaii)
Destructive volcanic mudflow that occurs when ash mixes w/ water or snow:
Lava with a smooth ropy surface that cools slightly on the top layer and wrinkles:
Pahoehoe (“Twisted braid of rope”)
What tectonic plate boundary are most volcanoes associated with?
Divergent plate boundaries
Effusive eruptions occur in what 2 volcano types?
1) shield volcanoes
2) fissure volcanoes
Which lava compositions have only a small amount of silica?
Ultramafic, mafic (thin/fluid-like…hot lava)
A submarine volcano in Hawaii that should appear at the surface in several thousands of years:
What forms in effusive eruptions after flood basalts cool and separate?
Columnar joints
What happens once a volcano migrates off of a hot spot?
It becomes extinct
What composition magma is beneath the Mt. St. Helens volcano, and why?
Felsic – very sticky magma makes for explosive eruptions
Which explosive type of volcano is composed almost exclusively of pyroclastic debris?
Cinder cone
Volcanic eruption with very hot, fluid-like magma that is ultramafic/mafic in composition and has a low amount of silica:
Effusive eruptions
What type of volcano is Mount St. Helens classified as?
Composite volcano (or stratovolcano)
Volcanic eruptions on the sides of mountains:
Flank eruptions
Which volcano type is the largest of all volcanoes?
Composite cones (Stratovolcanoes)
Volcanoes that form around the Pacific plate:
Pacific Ring of Fire
Space within a volcano that fills with magma and builds up pressure over time:
Magma chamber
Small pyroclastic material that is the size of a sand grain:
Volcanic ash
Chunky, blocky lava w/ a rough, jagged surface:
Aa (“ouch ouch”)
What is formed as igneous rocks cool and develop shrinkage fractures in pillar-like fashion?
Columnar joint
An enlarged volcanic crater:
Caldera (1 kilometer)
Fast-moving clouds of hot gas and ash that travel down the sides of a volcano:
Ash flows (nu’ee ardente)
The presence of pillow lava is evidence of what volcanic circumstance?
A submarine volcanic eruption
What is the only type of volcano that doesn’t build a cone-shaped mountain?
Fissure eruption volcano
List 2 volcanoes that are located over hot spots:
1) All Hawaiian volcanoes
2) Yellowstone volcano
What often causes craters to turn into calderas?
Sometimes the sides of the crater will cave in, which causes it to increase in size (1 kilometer).
What factor primarily controls the viscosity, and therefore the explosiveness, of magma?
Silica content, temperature
What type of lava serves as great evidence of plate tectonics?
Pillow lava
An upwelling of abnormally hot rocks within the Earth's mantle that are thought to be the cause of volcanic centers known as hot spots:
Mantle plumes
What is the most famous set of volcanic arc volcanoes?
Cascade Volcanoes (includes Mt. St. Helens and Mt. Rainier)
An active composite cone volcano located in Costa Rica:
Large, coarse fragments of pyroclastic debris:
Why do eruptions differ from one another?
1) Amount of gas – the more gas in the lava, the more explosive the eruption
2) Viscosity – temperature, silica content
What is one of the most famous columnar joints in the world?
Devil’s Tower (Wyoming)
Which type of volcano has hot fluid-like lava and often erupts from both the top and the sides?
Shield volcano
Which lava compositions have a high viscosity?
Intermediate, felsic (thick /sticky…cool lava)
Volcanic eruption that is associated w/ tons of pyroclastic debris, including ash fall, ash flow, and lahars:
Explosive eruption
Volcano type similar to that of a shield volcano; creates a quiet eruption w/ thin, fluid-like lava flow:
Fissure eruption volcano
A “glowing cloud” of hot ash flow:
Nuée ardente
What types of volcanic eruptions produce flood basalts and columnar joints?
Effusive eruptions
Volcano that is formed from alternating layers of lava & pyroclastic material that are created over a long period of time:
Composite cones (stratovolcanoes)
When does a crater change into a caldera?
When its diameter becomes greater than 1 kilometer
What type of volcano is Mauna Loa in Hawaii?
Shield volcano
A measure of magma’s resistance to flow:
Points on the Earth’s surface where volcanoes do not appear to be located on plate boundaries:
Volcanic hot spots
What destroyed the city of St. Pierre during the explosive 1902 eruption of Mount Pele?
Nuée ardente (volcanic ash flow)
A very steep-sided, symmetrical volcano that forms from an explosive eruption:
Cinder cone
What is the one of the Cascade Volcanoes that is not a composite cone (stratovolcano)?
Mt. Lassen (it is a volcanic dome)
What are the 2 types of shield volcano lava flows?
1) pahoehoe
2) aa
What is the relation between the violence of an eruption and its frequency?
Explosive eruptions occur less frequently.
The time between eruptions is considered the "pressure-building" period when gases and vapor pressure builds, resulting in very explosive eruptions.
Pyroclastic material that is the size of gravel:
A cone-shaped mountain that erupts lava and pyroclastic material:
Explosive eruptions occur in what 2 volcano types?
1) cinder cones
2) composite cones
Volcano that forms when a magma chamber never has enough pressure or gas to explode; magma slowly leaks down the tops & sides of the mountain:
Volcanic domes (Mt. Lassen)
Which lava compositions have a low viscosity?
Ultramafic, mafic (thin/fluid-like…hot lava)
A circular depression at the top of a volcano; leaves behind a hole:
What type of volcanic eruption contains a lot of water and produces large amounts of hot steam?
Phreatomagmatic eruptions
An active composite cone volcano located in Italy; best known for its 79 A.D. eruption in Pompeii:
Mt. Vesuvius
The largest pyroclastic material forms when blobs of lava harden in mid-air before falling back down to the earth. These hardened blobs often are one foot or greater in size. What name is given to these features?
Volcanic bombs