Igneous Rocks

Which three minerals are usually found in granite?

• biotite, olivine, and hornblende

• quartz, pyroxene, and olivine

• potassium feldspar, quartz, and hornblende

• plagioclase feldspar, biotite, and pyroxene

Which statement best describes the formation of an intrusive igneous rock?

• A. Magma solidifies slowly, resulting in a coarse-grained texture.

• B. Magma solidifies slowly, resulting in a fine-grained texture.

• C. Magma solidifies rapidly, resulting in a glassy texture.

• D. Magma solidifies rapidly, resulting in a clastic texture.

Dolostone and granite are similar because both are

• monomineralic

• clastic

• foliated

• crystalline

Rock B most likely is

• conglomerate

• schist

• obsidian

• peridotite

Which extrusive igneous rock is composed of approximately 40% quartz, 20% potassium feldspar, 20% plagioclase feldspar, 10% biotite mica, and 10% hornblende?

• rhyolite

• gabbro

• granite

• basalt

For an igneous rock to be classified as rhyolite, it must be light colored, be fine grained, and contain

• quartz

• calcite

• pyroxene

• olivine

Compared to felsic igneous rocks, mafic igneous rocks contain greater amounts of

• white quartz

• aluminum

• pink feldspar

• iron

The accompanying photograph shows actual crystal sizes in a light-colored igneous rock that contains several minerals, including potassium feldspar, quartz, and biotite mica. The rock should be identified as

• granite

• gabbro

• basalt

• rhyolite

When granite melts and then solidifies, it becomes:

• a sedimentary rock

• an igneous rock

• a metamorphic rock

• sediments

Tags

NGSS.MS-ESS2-1

NGSS.MS-PS1-4

Which two rocks have the most similar mineral composition?

• marble and rhyolite

• limestone and basalt

• quartzite and rock salt

• granite and phyllite

Tags

NGSS.MS-ESS3-1