Igneous Rocks

An igneous rock is one that

• has crystallised at the Earth's surface

• has crystallised well below the Earth's surface

• contains either abundant quartz or glass

• all of the above

A silicate magma rich in iron and magnesium

• silicic

• mafic

• hydrous

• vesicular

A very coarse-grained igneous rock believed to form from fluid-rich magmas

• pegmatite

• porphyry

• glassy

• basalt

The volcanic (extrusive) equivalent of gabbro

• rhyolite

• basalt

• andesite

• obsidian

Plutonic igneous rocks cool FASTER / SLOWER than volcanic igneous rocks

• FASTER

• SLOWER

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

Pyroclastic rocks are composed of

• lava

• crystals only

• fragments of magma and pre-existing rocks

• rocks only

A runny magma (low viscosity) will tend to produce a

• coarse-textured rock because minerals will assemble easily

• coarse-texted rock because the atoms will move more freely

• fine-textured rock because the atoms will move less freely

• fine-textured rock because the minerals will assemble easily

Felsic magmas have HIGH / LOW amounts of silica

• HIGH

• LOW

Magmas that cool very slowly will tend to produce a COARSE / FINE grain rock because the grain size is LARGE / SMALL

• COARSE, SMALL

• FINE, SMALL

• FINE, LARGE

• COARSE, LARGE

Tags

NGSS.MS-PS1-4

Aphanitic rocks cool

• have pyroclastic material and cool quickly deep below Earth's surface

• slowly on top of the surface

• slowly with a fine-grained texture

• quickly on top of the surface