Exam 4: Igneous Rocks and Intrusive Igneous Activity

Trapped gases in cooling lava form cavities called ____________________.Cinder cones may contain large amounts of ____________________,which contains more of these cavities than it does rock.

What is viscosity?

Igneous rocks with a two-stage intrusive-extrusive origin are recognized by a texture that is:

Plutons form within the peaky structure of a volcano.

What role does stoping play in the emplacement of batholiths?

Rapid cooling of magma results in a(n)____________________-grained texture called ____________________.

Igneous rocks of dark color are generally rich in the chemical elements ____________________ and ____________________,while those of light color are generally rich in ____________________ and ____________________.

Igneous rocks with a texture that is so fine-grained that the crystals are too small to see is:

What phenomena does Bowen's reaction series help explain?

Although all compositions are represented,most plutons are:

When magma cools slowly,crystal growth proceeds at a relatively ____________________ speed,and the resultant rock is ____________________ in texture.

The process of assimilation partly explains why felsic intrusive rocks are much more common than mafic intrusive rocks.

Tuff is made up of pyroclastic materials.

What is a mantle plume,and what causes one to erupt?

Most igneous rocks are classified by:

How does a dike differ from a sill?

Briefly explain how it is possible for a single magma to yield rocks of felsic,intermediate,and mafic composition.

Concordant tabular sheetlike plutons are called ____________________,whereas discordant tabular plutons are called ____________________.

A vesicular felsic rock is called a:

Hotspot volcanism is likely the result of