Igneous Rocks
Question 4 1.5 / 1.5 points If a body of magma becomes more felsic, its viscosity will ____________. Question options: increase decrease stay the same
increase
Question 2 1.5 / 1.5 points Igneous rocks ____________. Question options: are formed through the freezing of melt can be produced at the surface of the Earth as well as deep below the surface are the most common type of rocks within Earth all of the above
all of the above
Question 6 1.5 / 1.5 points As compared to coarse-grained igneous rocks, all fine-grained igneous rocks ____________. Question options: cool and solidify more quickly cool and solidify more slowly solidify at higher temperatures solidify at lower temperatures
cool and solidify more quickly
Question 7 1.5 / 1.5 points All other factors being equal, intrusive rocks that form deep within Earth ____________ than intrusive rocks that cool near the surface. are more felsic contain a smaller proportion of volatiles cool more slowly cool more rapidly
cool more slowly
Question 3 1.5 / 1.5 points When magma crystallizes, ____________ are formed. Question options: intrusive igneous rocks extrusive igneous rocks volatiles pyroclastic debris
intrusive igneous rocks
Question 1 1.5 / 1.5 points The difference between lava and magma is that ____________. Question options: magma is light in color and lava is dark magma usually has mafic composition and lava usually has felsic composition magma is found beneath the Earth's surface, whereas lava has reached the surface magma flows more quickly than lava
magma is found beneath the Earth's surface, whereas lava has reached the surface
Question 5 1.5 / 1.5 points When rock is partially melted, the chemistry of the melt is ____________. Question options: more mafic than the original chemistry of the rock that was partially melted more felsic than the original chemistry of the rock that was partially melted identical to the original chemistry of the rock that was partially melted completely unpredictable (it could be more mafic or more felsic
more felsic than the original chemistry of the rock that was partially melted
Question 9 1.5 / 1.5 points In Bowen's discontinuous reaction series, the first mineral to crystallize from a mafic melt is ____________. Question options: olivine plagioclase pyroxene quartz
olivine
Question 10 1.5 / 1.5 points An igneous rock with a mixed texture of coarse grains (phenocrysts) surrounded by fine crystals (groundmass) is termed ____________. Question options: porphyritic phaneritic aphanitic necrotic
porphyritic
Question 8 1.5 / 1.5 points Coarse-grained granite is most similar in mineral composition to fine-grained ____________. Question options: andesite basalt komatiite rhyolite
rhyolite