Chapter 7 quiz & hw

q13: On the graph shown, what do the numbered, dashed lines indicate? A. the metamorphic facies a rock will pass through if it is buried in different tectonic settings B. All of the possible answers are correct. C. geothermal gradients associated with different tectonic settings D. how temperature changes with depth in different tectonic settings

All of the possible answers are correct.

q1: Hydrothermal fluids A. can change a rock's chemical composition in a process known as metasomatism. B. are chemically active solutions that can dissolve and transport ions. C. All of the possible answers are correct. D. consist of hot water, steam, and supercritical fluid.

All of the possible answers are correct.

q16: Which of the following locations could possible be part of a shield? A. Iceland B. Canada C. Japan D. Hawaii

Canada

q9: What is most likely true of a metamorphic rock that exhibits significant compositional banding, such as the one shown here?

It is a foliated rock called gneiss.

h14: Geologists use the term "metamorphic grade" to indicate the amount or degree of metamorphic change. The diagram shows seven rocks. Drag and drop three of the statements to the correct rock's target.

Left to right: -Low-grade rock used for roofing shingle -Intermediate-grade rock with coarse mica -High-grade rock with compositional banding formed without melting

h10: Sort each of the following metamorphic rocks according to its protolith.

Limestone: marble Mudstone: schist & phyllite Sandstone: quartzite Conglomerate: metaconglomerate

h13: Match the following geologic settings to the form of metamorphism which occurs at that location.

Mid-Ocean Ridge: Hydrothermal Mountain Range Core: Dynamo-Thermal Ten miles below the surface:Burial Fault Zone: Dynamic Intrusion of pluton: Thermal Meteorite impact site: Shock

q6: Recrystallization

changes the texture (shape and size) of the grains.

q10: What type of foliation does slate, a common material used for roof shingles, exhibit?

cleavage

q20: Shields are

composed of some of the oldest rock on the Earth

q18: Subduction zone metamorphism

forms the metamorphic rock blueschist

h9: This chart shows that certain minerals form at different metamorphic grades and that the mineral assemblages can vary depending on the composition of the protolith. Please use the chart to rank the mineral assemblages in order from highest grade to lowest grade.

highest 1. garnet, feldspar, and sillimanite 2. garnet, staurolite, and muscovite 3. chlorite, quartz, and biotite 4. clay and chlorite lowest

q11: Which of the following rocks is nonfoliated ? A. schist B. hornfels C. phyllite D. slate

hornfels

q12: Quartzite

is basically a solid mass of interlocking quartz grains

q17: Mylonite, such as the example shown here,

is produced by shear stress on softened rock.

h2: Phase changes create polymorphs of the original mineral. What is the polymorph of andalusite at 7 kbars of pressure and 450°C?

kyanite

q7: What is the protolith of marble?

limestone

q15: The rocks on this map that underwent the deepest burial are now exposed at the surface in which state?

massachusetts

q14: Identify the list of rock types that is ordered by increasing degrees of metamorphism (i.e., from lower to higher grade).

slate, phyllite, schist, gneiss

h11: This image shows a cut and polished sample of gneiss, a high-grade foliated metamorphic rock. Which of the following processes can be responsible for the development of compositional banding?

-compositional differences in the protolith that are stretched and smeared out -segregation of minerals into bands of different composition

h5: Order the steps in neocrystallization

1. protolith minerals are consumed by chemical reactions. 2. thin clay minerals begin to align. 3. clay grains flatten out and become parallel to one another. 4. small garnets appear.

h6: Identify outcomes of metamorphic change.

- changes in mineral size and shape - growth of new minerals - phase change of minerals - creation of foliation

h3: Cite factors that can result in metamorphism.

- hydrothermal fluids - increases temperature - increased pressure

h7: Which of the compressional stress orientations shown in the images below produced the foliation shown in the photo above?

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h8: Watch the Neocrystallization topic of the Metamorphic Change Animation. The protolith of the rock undergoing neocrystallization is a mudstone. As metamorphism proceeds, it is turned into a metamorphic rock called a schist. Based on what you can see in the animation, which of the following occur(s) during this transition?

-Existing minerals undergo plastic deformation. -Existing minerals become elongated and take on a foliation -Neocrystalline garnets form.

q19: Which of the following statements about metamorphic rocks and their characteristic environments is true? A. Slate, phyllite, schist, and gneiss are found in areas of continental collision. B. Hornfels is a result of burial metamorphism. C. Blueschists are found in the mid-ocean ridge. D. Foliated metamorphic rocks are usually found in contact aureoles surrounding plutons.

Slate, phyllite, schist, and gneiss are found in areas of continental collision.

h1: Watch the Pressure Solution topic of the Metamorphic Change Animation, and then label the diagram.

Top to bottom: - pore space -grain - grain-to-grain boundary -new precipitation -dissolution

h4: Choose the statement that best describes foliation.

an alignment of mineral grains perpendicular to the direction of compression

q2: a metamorphic rock

may have preferred mineral orientation caused by differential stress.

q5: Shear stress

moves material parellel to a surface.

q4: Which of the following is a common process during metamorphism? A. lithification B. pressure solution C. brittle deformation D. melting

pressure solution

h12: The metamorphic rock shown below is best classified as

schist.

q8: What is the name of the type of foliation that is defined by the preferred orientation of large mica flakes, as shown in the photo (looking down on the foliation plane)?

schistosity

q3: In this image of a metamorphic rock viewed through a petrographic microscope, the preferred orientation of the mineral grains is ________, indicating that the direction of greatest compression was oriented ________.

vertical; horizontally