The two categories of the Environment of Formation are:

• Extrusive and Intrusive

• Crystal Size and Texture

• Texture and Intrusive

• Crystal Size and Extrusive

Which processes lead directly to the formation of igneous rock?

• weathering and erosion

• compaction and cementation

• heat and pressure

• melting and solidification

Which texture best describes an igneous rock that formed deep underground?

• glassy

• vesicular

• fine grained

• coarse grained

Obsidian's glassy texture indicates that it formed

• quickly, on Earth's surface

• quickly, deep below Earth's surface

• slowly, on Earth's surface

• slowly, deep below Earth's surface

Tags

NGSS.MS-PS1-4

The flowchart illustrates the change from melted rock to basalt. The solidification of the melted rock occurred

• rapidly, resulting in coarse-grained minerals

• rapidly, resulting in fine-grained minerals

• slowly, resulting in fine-grained minerals

• slowly, resulting in coarse-grained minerals

Tags

NGSS.MS-ESS2-1

Which igneous rock is dark colored, cooled rapidly on Earth's surface, and is composed mainly of plagioclase feldspar, olivine, and pyroxene?

• obsidian

• rhyolite

• gabbro

• scoria

The photograph shows an igneous rock. What is the origin and rate of formation of this rock?

• plutonic with rapid cooling

• plutonic with slow cooling

• volcanic with rapid cooling

• volcanic with slow cooling

Which igneous rock has a vesicular texture and contains the minerals potassium feldspar and quartz?

• andesite

• pegmatite

• pumice

• scoria

Biotite mica and muscovite mica have different chemical compositions. Compared to the magma from which biotite mica forms, the magma from which muscovite mica forms is usually

• more felsic and more dense

• more felsic and less dense

• more mafic and more dense

• more mafic and less dense

Tags

NGSS.MS-PS1-2

The photograph shows the intergrown crystals of a pegmatite rock. Which characteristic provides the best evidence that this pegmatite solidified deep underground?

• low density

• light color

• felsic composition

• very coarse texture