magma is found beneath the Earth's surface, whereas lava has reached the surface
The difference between lava and magma is that _-.
A blob-like igneous rock body that has cooled beneath the surface of Earth is __.
a sheetlike intrusion that cuts across preexisting layers
A dike is __.
a sheetlike intrusion that lies parallel to surrounding layers of sedimentary rock
A sill is __.
intrusion formed within the magma chamber of volcano
A volcanic neck, such as that seen at Shiprock, New Mexico, is a(n) __.
fine-grained and coarse-grained igneous rocks
Geologically, melts are equivalent to both __.
all of the above (are formed through the freezing of melt, can be produced at the surface of Earth and below the surface, most common type of rock)
Igneous rocks __.
Very early in Earth's history, it was so hot that the surface was likely entirely molten.
be much hotter than at present
Radioactive isotopes, differentiation of Earth's iron core, gravity driven compression, and meteoric bombardment all caused early Earth to __.
Bombs, ash, and cinders are all examples of __.
intrusive igneous rocks
When magma crystallizes, __ are formed.
temperature with depth in Earth's interior
The geotherm is the rate of change of __.
loss of volatiles to the atmosphere
The formation of magma within Earth is NOT caused by which of the following processes?
more felsic than the source rock
If a body of igneous (source) rock is subjected to partial melting, the magma that is produced is expected to be __.
more felsic than the source rock
If a body of magma is subjected to fractional crystallization, the rock that results is expected to be __.
have a tendency to evaporate and are stable as gases
Volatiles refer to substances that __.
If the volatile content of magma is increased, its viscosity will __.
If a body of magma becomes more felsic, tis viscosity will __.
All of the Earth's internal heart was acquired very early in its history through meteoric impact and differentiation of the core. The Earth's interior loses heat to space but does not currently receiving heat through any known process.
more felsic than the original chemistry of the rock that was partially melted
When rock is partially melted, the chemistry of the melt is _.t
A volcano emits ash, which falls from the sky, settles in layers, and is eventually cemented. The resultant rock is termed __.
Due to fractional crystallization and assimilation of surrounding host rock, most magmas that rise slowly through the rust chemically evolve to become __.
cool and solidify more quickly
As compared to coarse-grained igneous rocks, all fine-grained igneous rocks __.
solidify at lower tempatures
As compared to mafic igneous rocks, all felsic igneous rocks __.
cool more slowly
All other factors being equal, intrusive rocks that form deep within Earth __ than intrusive rocks that cool near the surface.
possess exceptionally coarse grains
Pegmatites, which occur in dikes, are unusual among shallow intrusive rocks in that they __.
all of the above (is volcanic glass, possess conchoidal fracture, typically is felsic in composition)
Ash and lava fragments that cascade down the sides of a volcano eventually settle and lithify to form __.
Volcanoes that do not occur along either present or emergent plate boundaries are associated with __.
A famous example of hot-spot volcanism occurs at __.
the Aleutian Islands of Alaska
An island volcanic arc occurs at __.
the Andes Mountains
A continental volcanic arc occurs at __.
Coarse-grained granite is most similar in mineral composition to fin-grained __.
Coarse-grained diorite is most similar in mineral composition to fine-grained __.
Coarse-grained gabbro is most similar in mineral composition to fin-grained __.
are lighter in color than mafic rocks
Most commonly, felsic igneous rocks __.
erupt underwater and thus cool very quickly
Pillow basalts attain their distinctive blob-like shapes because their parent lavas do not travel far prior to solidification. This is because the parent lavas __.
pieces of surrounding country rock are broken off and assimilated
Stoping by magmas occurs when __.
A majority of the melts in the Earth form through the partial melting of ultramafic mantle rock. These newly-formed magmas are __.
As compared to aphanitic igneous rocks, phaneritic rocks are __.
magma is found beneath the surface, lava at the surface
The difference between magma and lava is __.
water and carbon dioxide
Important volatiles in magmas include __.
Which type of magma has the greatest silica content?
Which type of magma has the greatest iron and magnesium content?
Which type of magma is produced at the coolest temperatures?
When rock is melted within Earth, typically the entire volume of rock is transformed from solid state to a liquid.
In Bowen's discontinuous reaction series, the first mineral to crystallize from a mafic melt is __.
Bowen's continuous reaction series describes the crystallization behavior of a single mineral (with variable chemical composition), __.
The silicate mineral that is found in the greatest variety of igneous rocks is __.
An igneous rock with a mixed texture of coarse grains (phenocrysts) surrounded by fine crystals (groundmass) is termed __.
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