|
Rhyolitic |
Which of the following types of magma has the highest viscosity? |
|
Amount of gas in the magma |
In addition to viscosity, which of the following parameters has an influence on whether a volcanic eruption will be effusive or violent? |
|
Basaltic |
Which of the following types of lava will most likely lead to a volcanic eruption of the effusive state? |
|
Violent and explosive |
The subduction of oceanic crust under continental crust predominantly produces which of the following types of volcanic eruption? |
|
Quiet and effusive |
A hot spot that occurs in oceanic crust is likely to produce which of the following types of eruptions? |
|
The lava is more fluid |
Why are shield volcanoes wider than composite volcanoes? |
|
Decompression melting and wet melting (the addition of volatiles) |
Which two processes commonly generate magma? |
|
Water contained within minerals in the subducting plate is released in metamorphism |
Where does the water involved in melting at subduction zones come from? |
|
The rock making up the mantle |
What is peridotite? |
|
The addition of water lowers the melting temperature of rock |
Why is water a necessary component of the melting process in subduction zones? |
|
Tectonic plates are moving apart at mid-ocean ridges, resulting in a lowering of pressure beneath the ridge. Tectonic plates are moving together at subduction zones, resulting in an increase of pressure under new mountains. |
Why is decompression melting common at mid-ocean ridges but not at subduction zones? |
|
Increase in temperature |
Which of the following could cause rock to melt? |
|
Continental rifts, continental arcs, island arcs, mantle plumes |
Which of the following are common tectonic settings associated with volcanic activity? |
|
Eastern Africa rift valley |
Which of the following is a present-day example of continental rift? |
|
New ocean basin |
Which of the following often forms after continental rifting? |
|
On the overriding plate near a subduction zone |
Where are continental volcanic arcs found? |
|
Arc magmas are more viscous than rift magmas |
How are continental rift magmas and continental arc magmas different? |
|
Both are formed near subduction zones |
How are island arc and continental arc magmas similar? |
|
Mariana Islands |
Which of the following are examples of modern day island-arcs? |
|
A circular column of magma that rises from deep within Earth |
What is a mantle plume? |
|
Hawaiian Islands |
Which of the following is an example of a modern-day mantle plume volcanism? |
|
Out pourings of lava/magma originating from the mantle |
The production of magma at divergent boundaries is characterized by which of the following? |
|
Composition |
What primary factors determine the nature of volcanic eruptions? |
|
Lahar |
What destructive forces are associated with composite volcanoes? |
|
Pyroclastic flow |
What term describes hot mixtures of gas, ash, and pumice that race down the flanks of volcanoes at speeds up to 125 mi/hr? |
|
Shield volcano |
Which of the following are types of volcanoes? |
|
Shape |
What information do geologists use to classify volcanoes? |
|
Pyroclastic deposites |
Cinder cones are made of __________. |
|
Most cinder cones erupt once |
In general, how often do most cinder cones erupt? |
|
Basalt flows |
What are shield volcanoes generally made of? |
|
300-10,000 meters |
What is the range of a shield volcano height? |
|
Basalt flows |
What are composite volcanoes made of? |
|
The lava that flows out of shield volcanoes is more fluid |
Why are shield volcanoes wider than composite volcanoes? |
|
Shield volcanoes |
What types of volcanoes are the highest? |
|
500-2,000 meters |
What is the range of a dome complex height? |
|
Composite volcanoes |
Which of the following volcanic forms best describes nearly symmetrical structures composed of interbedded lavas and pyroclastic material primarily deposited from a central vent? |
|
Cinder cones |
Which of the following volcanic types produces small, steep-sided structures composed of pyroclastic material? |
|
Mantle plumes |
At which type of tectonic setting would you expect the development of shield volcanoes? |
|
An oceanic plate subducted beneath a continental plate |
At which type of tectonic setting would you expect the development of composite volcanoes? |
|
Basaltic |
In which of the following lava types would you expect to see the development of a pahoehoe? |
|
Rhyolitic |
In which of the following lava types would you expect to find the greatest percentage of gases? |
|
Bombs |
What do we call pyroclastic material, ejected during a volcanic eruption, composed of incandescent lava greater than 64 mm in diameter? |
|
Water Vapor |
Which of the following gases is most abundant in basaltic lavas? |
|
Subduction of oceanic plate under a continental plate |
At which of the following tectonic settings would you expect to find volcanoes producing the highest volumes of pyroclastic material? |
|
Mantle plumes |
At which of the following tectonic settings would you expect to find volcanoes producing significant amounts of very fluid, high temperature lavas? |
|
Andesite |
What type of lava is considered intermediate in composition? |
|
Composite volcanoes |
Which of the following volcanic forms best describes large, nearly symmetrical structures composed of interbedded lavas and pyroclastic material primarily deposited from a central vent? |
|
Cinder cones |
Which of the following volcanic types typically produces small, steep-sided structures composed of pyroclastic material? |
|
Lahars |
What do we call mudflows produced by the melting of snow and glaciers on composite volcanoes? |
|
Mantle plumes |
At which type of tectonic setting would you expect the development of shield volcanoes? |
|
An oceanic plate subducted beneath a continental plate |
At which type of tectonic setting would you expect the development of composite volcanoes? |
|
Felsic; coldest and has the most silica |
Which of the following magmas has the greatest viscosity and why? |
|
Water vapor |
Which of the following substances makes up the largest percentage of volcanic gases in magma? |
|
Basaltic magma, low viscosity |
What magma composition and viscosity is associated with shield volcanoes? |
|
Basaltic lava, loose cinders |
Describe the state and composition of cinder cone volcanoes. |
|
Andesitic |
Which magma is most associated with composite volcanoes? |
|
Water |
Which factor would increase the velocity and severity of a lahar? |
|
A massive eruption resulted in collapse of the magma chamber |
Which of the following scenarios resulted in the creation of Crater Lake? |
|
Subduction zones |
Rocks melt due to the introduction of water mainly at _______. |
|
Water boiled out of subducted oceanic plates and melted mantle material |
Which two processes can contribute to generating magma at a convergent plate boundary? |
|
Andesitic |
What type of magma is considered to be intermediate in composition? |
|
Plate boundaries |
The location of most volcanoes closely correlates with _____. |
|
Intraplate volcanism usually erupts basaltic lava. |
Which of these is true about intraplate volcanism? |
|
volcanism caused by convergent oceanic-continental boundaries |
What type of volcanism characterizes the Ring of Fire? |
|
Divergent oceanic-oceanic |
What type of boundary is present along the Eastern boundary of the North American plate? |
|
Oceanic hot-spot |
At what tectonic setting is Hawaii located? |
|
Decompression melting |
What drives melting at divergent boundaries? |
|
Transform boundary |
Which of the following tectonic settings does NOT produce volcanism? |
|
Cone-shaped volcano with alternating layers of lava and pyroclastic material |
Which of the following would best describe the shape and composition of a volcano in the Cascade Range? |
Share This
Flashcard
