Igneous Rock Exam

Front

What is the environment of formation for igneous rocks with a grain size less than 1 mm?

Back

Above ground (extrusive environment)

Front

What type of igneous rock forms in an intrusive environment?

Back

Intrusive igneous rocks form below ground.

Front

Which mineral is most commonly found in felsic igneous rocks?

Back

Quartz

Front

What texture is characteristic of glassy igneous rocks?

Back

Glassy texture is smooth and shiny, with no visible crystals.

Front

What is the texture of igneous rocks with a grain size less than 1 mm?

Back

Fine texture.

Front

What are the two main types of igneous rocks based on their formation environment?

Back

Intrusive and extrusive igneous rocks.

Front

What is the primary characteristic of intrusive igneous rocks?

Back

They form from magma that cools slowly below the Earth's surface.

Front

What is the primary characteristic of extrusive igneous rocks?

Back

They form from lava that cools quickly on the Earth's surface.

Front

What is the difference between felsic and mafic igneous rocks?

Back

Felsic rocks are rich in silica and light-colored, while mafic rocks are low in silica and dark-colored.

Front

What is vesicular texture in igneous rocks?

Back

Vesicular texture contains small gas bubbles, giving it a porous appearance.