Exam 4: Magma, Igneous Rocks, and Intrusive Activity

At what temperature will peridotite melt along the geothermal gradient?

What role does water play in generating magma?

If an igneous rock is heated, which mineral will be the very last mineral left to melt according to the Bowen's reaction series?

Refer to the scenario above.How would you expect the geothermal gradient to change if this borehole were drilled near Yellowstone National Park? Why?

Dikes tend to form as solitary structures.

A ________ is a mushroom-shaped pluton that forms by injecting magma between sedimentary strata, forcing the upper layers to arch upward.

In the process of a magma cooling and crystallizing, if the original melt contained large amounts of iron, why isn't quartz a ferromagnesian mineral?

Welded tuff consists of ash surrounding large, jagged, irregularly-shaped pieces of material.What is this material and where does it come from?

What is the name of the preexisting rock through which intrusive igneous bodies intrude?

What was the rate of cooling and the environment of formation for an extrusive igneous rock and why?

What are two ways a primary magma can be generated?

How will mantle-derived magma change when it ponds against crustal rocks?

Concordant plutons cut across existing structures while discordant plutons are parallel to existing features.

Which two minerals define a felsic composition?

Which mineral group makes up most igneous rocks?

A ________ is a tabular, concordant pluton that is nearly horizontal and forms when magma exploits a weakness between sedimentary layers.