Problem 1
Would you expect all the crystals in an intrusive igneous rock to be the same size? Explain why or why not.
Problem 3
Is it possible for two igneous rocks to have the same mineral composition but be different rocks? Use an example to support your answer.
Problem 5
The statements that follow relate to terms used to describe igneous rock textures. For each statement, identify the appropriate term. a. Openings produced by escaping gases b. The texture of obsidian c. A matrix of fine crystals surrounding phenocrysts d. Consists of crystals that are too small to be seen without a microscope e. A texture characterized by two distinctly different crystal sizes f. Coarse grained, with crystals of roughly equal size g. Exceptionally large crystals, most exceeding 1 centimeter in diameter
Problem 7
A common misconception about Earth's upper mantle is that it is a thick shell of molten rock. Explain why Earth's mantle is actually solid under most conditions.
Problem 8
Describe two mechanisms by which mantle rock can melt without an increase in temperature. How do these magma-generating mechanisms relate to plate tectonics?
Problem 11
Each of the following statements describes how an intrusive feature appears when exposed at Earth's surface due to erosion. Name the feature. a. A dome-shaped mountainous structure flanked by upturned layers of sedimentary rocks b. A vertical wall-like feature a few meters wide and hundreds of meters long c. A huge expanse of granitic rock forming a mountainous terrain tens of kilometers wide d. A relatively thin layer of basalt sandwiched between horizontal layers of sedimentary rocks exposed along the walls of a river valley
Problem 12
Mount Whitney, the highest summit (4421 meters [14,505 feet]) in the contiguous United States, is located in the Sierra Nevada batholith. Based on its location, is Mount Whitney likely composed of granitic, andesitic, or basaltic rocks?
