Metamorphic Rock and Resources, Metamorphic Study Guide

T

Calcite is the main mineral constituent of the sedimentary rock limestone and of the metamorphic rock marble.

T

Every metamorphic rock has a parent rock from which it formed.

hydrothermal veins

The minerals gold, silver and mercury are often found in ________. a. alteration of limestone b. hydrothermal veins c. disseminated deposits d. the lower parts of an intrusion

slate

Which low-grade metamorphic rock composed of extremely fine-sized mica and other mineral grains, typically exhibits well-developed rock cleavage? a. slate b. quartzite c. hornfels d. schist

contact

Which type of metamorphism occurs specifically in the heated zone around a pluton or other body of magma?

marble

nonfoliated metamorphic rock consisting of mostly calcite a. hornfels b. marble c. gneiss d. phyllite

coal forms in swamps and oil/gas form in marine environments

A major difference between coal and oil/gas is ________. a. coal forms in deep marine environments and oil/gas form in shallow marine environments b. coal forms in shallow marine environments and oil/gas form in swamps c. coal forms in swamps and oil/gas form in marine environments d. coal forms on land from dinosaurs and oil/gas form from ancient fish

by regional metamorphism of volcanic rocks such as andesite and basalt

Amphibolite is a foliated metamorphic rock composed principally of hornblende and plagioclase. How does it form? a. by the impact of an asteroid on interbedded sandstone and shale b. by gouging and crushing of limestone along a fault c. by contact metamorphism of sandstone along the contact with granitic batholith d. by regional metamorphism of volcanic rocks such as andesite and basalt

F

At high pressures and elevated temperatures of regional metamorphism, silicate rocks are more resistant to flowage and deformation than at low temperatures and pressures.

fluids that readily change to gases at surface conditions

Chemically active fluids are ________. a. fluids that readily change to gases at surface conditions b. fluids that contain large quantities of oxygen which reacts with most minerals to form new minerals during metamorphism c. more basic than regular fluids d. more acidic than regular fluids

forces are applied equally in all directions

Confining pressure is where ________. a. pressure is applied in a cubic region b. forces are applied equally in all directions c. pressure is parallel to the bedding planes d. forces are applied from the top and the bottom equally

T

During metamorphism, the material undergoing deformation remains a solid.

aid in the movement of dissolved silicate constituents and facilitate growth of the minerals grains

During metamorphism, what is the major effect of chemically active fluids? a. increase the pressures in deeply buried, regional-metamorphic zones b. prevent partial melting so solid rocks can undergo very high temperature regional metamorphism c. facilitate the formation of schistosity and gneissic banding in hornfels and slates d. aid in the movement of dissolved silicate constituents and facilitate growth of the minerals grains

F

Foliated metamorphic rocks are composed largely of equidimensional grains of minerals such as quartz and calcite.

the pre-metamorphic rock was a shale or mudstone containing organic matter

Granite is identified in a particular schist. Which one of the following conclusions is justified? a. the graphite lubricated shearing movements along a fault causing a schist to form b. the rock also contain diamonds; both are crystalline forms of the element carbon c. the pre-metamorphic rock was a shale or mudstone containing organic matter d. the schist formed from a quartz rich sedimentary limestone

T

High-grade regional metamorphism produces significant and recognizable changes in the textures and mineral compositions of rocks.

100°C

In an area where the temperature increase with depth averages 20°C per kilometer, the temperature at a depth of 5 kilometers would be ________. a. 20°C b. 50°C c. 100°C d. 200°C

T

In general, recrystallization tends to produce larger crystals.

permeability and porosity

In order to get oil and gas in sufficient quantities to make a profit, an oil trap must exist with ________. a. lateral continuity that allows fluids to migrate b. shale with little or no sulfur c. no fractures or structure d. permeability and porosity

at great depths in the crust where two continents are colliding

In which setting would regional metamorphism be most likely? a. at great depths in the crust where two continents are colliding b. at shallow depths below a oceanic ridge or rift zone c. at shallow depths along major transform faults in the continental crust d. at shallow depths beneath the seafloor where water pressures are immense

chromite

Magma differentiation tends to produce deposits of ________ near the base of intrusions.

F

Metamorphism can affect only sedimentary rocks.

experiences conditions that are significantly different from those that formed the rock

Metamorphism occurs when a rock ________. a. experiences conditions that include high pressures b. experiences conditions that include high temperatures c. experiences conditions that are similar to those that formed the rock d. experiences conditions that are significantly different from those that formed the rock

F

Most of the energy and mineral resources we use are renewable.

all of the above

Mountain building causes metamorphism because _____________. a. mountains are heavy and they push shallow, cool rocks to depths where they get heated b. mountains form by the gradual buildup of material that comes from other areas and this can produce an uneven pressure on rocks c. mountains are heavy and they compress the rocks under them. d. all of the above

direction perpendicular to the compressional stress

Recrystallization during metamorphism causes grains to grow longer in the ________. a. direction of maximum differential stress b. direction perpendicular to the compressional stress c. horizontal direction d. direction parallel to the compressional stress

T

Slate and schist are both derived from metamorphism of shales and mudstones.

denser

Slate is ________ than shale. a. darker b. more planar c. denser d. lighter

F

Slate is associated with high-grade metamorphism.

marble

The common rock produced by the metamorphism of limestone is ________. a. marble b. phyllite c. mica schist d. gneiss

slate

The low grade metamorphism of shale produces ________. a. schist b. gneiss c. marble d. slate

driving chemical reactions that lead to recrystallization

The major role of thermal energy (heat) in metamorphism is ________. a. driving chemical reactions that lead to recrystallization b. providing energy for the physical changes that occur during metamorphism c. increasing the processes of dissolution and flow of different minerals d. reducing the strength of rocks so that stress can be an effective agent of change

heat

The most important agent(s) of metamorphism, according to your text, is (are) ________. a. confining pressure b. heat c. differential stress d. chemically active fluids

heat

The primary agent of contact metamorphism is ________. a. folding b. strain c. stress d. heat

26.0 km

The quartz in granite begins to melt at 650°C, so if we find a migmatite where quartz has melted in a granitic rock and we know the temperature in the region increased with depth by about 25°C per kilometer, we could estimate the depth that the rock had been at to be about ________. a. 12.5 km b. 18.0 km c. 23.5 km d. 26.0 km

the final crystallizing parts of magma

The very large crystals of quartz, feldspar, and muscovite found in pegmatites form from ________. a. the middle crystallizing parts of a magma b. the final crystallizing parts of a magma c. the early crystallizing parts of a magma d. all of the above

phyllite

What foliated, metamorphic rock is texturally intermediate between slate and schist? a. phylitte b. quartzite c. gneiss d. fault breccia

heat from a nearby magma body

What is the major source of heat for contact metamorphism? a. heat from a nearby magma body b. heat from grinding and shearing on faults c. heat from the spontaneous decomposition of micas and feldspars d. deep burial and heat from the Earth's interior

calcite grains grow larger and increase in size

What major change occurs during metamorphism of limestone to marble? a. calcite grains grow larger and increase in size b. limestone grains react to form quartz and feldspar c. clays crystallize to micas, forming a highly foliated mica-rich rock d. calcite grains are dissolved away leaving only marble crystals

micas

What platy, parallel, mineral grains are the most visual aspect of foliated metamorphic rocks? a. feldspars b. micas c. carbonates d. quartz

marble and quartzite

What two, metamorphic rocks are composed predominately of single minerals? a. mica schist and granitic gneiss b. garnet schist and hornfels c. marble and quartzite d. fault breccia and graphitic schist

schistosity

What type of foliation results from the parallel alignment of abundant, coarse-grained mica flakes in a metamorphic rock? a. gneissic banding b. phyllitic structure c. slaty cleavage d. schistosity

shale or mudstone

What type of sedimentary rock is typically metamorphosed to form slates or phyllites?

foliated

When a metamorphic rock exhibits a layered or banded appearance, it is said to exhibit a(n) ________ texture.

flatten and elongate

When rocks experience high temperatures and differential stresses deep in the Earth, their grains tend to ________. a. break in small fragments like a piece of fine crystal b. flatten and elongate c. fracture along planes of weakness d. form new minerals

gneiss

Which metamorphic rock or rocks exhibit alternating layers or bands of different light-and-dark-colored minerals?

marble

Which metamorphic rock, widely used for monuments or buildings will deteriorate significantly in contact with acid rains?

pressures are fairly low, the rock is in the upper part of the crust, and heat is supplied from a near by magma body

Which of the following best describes the condition of contact metamorphism? a. pressures are fairly low, the rock is in the upper part of the crust, and heat is supplied from a near by magma body b. pressures are very high, the rock is deeply buried, and temperatures are raised by the Earth's internal heat c. depths are fairly shallow but temperatures and pressures are so high that the rock begins to partially melt d. heat is generated by shearing and mechanical movements along faults

all of the above

Which of the following changes may occur during metamorphism? a. the rock becomes more compact b. certain minerals may recrystallize c. crystals may grow larger d. all of the above

schist

Which of the following forms at the highest grade of regional metamorphism? a. phylitte b. slate c. hornfels d. schist

bedding planes and strata

Which of the following is not an example of a foliation in a metamorphic rock? a. parallel alignment of flattened pebbles b. bedding planes and strata c. parallel alignment of platy or flat minerals d. compositional banding

slate, phyllite, schist

Which of the following lists the rock in order of increasing grain size and increasing grade of metamorphism? a. slate, schist, phyllite b. slate, phyllite, schist c. schist, slate, phyllite d. phyllite, slate, schist

slate, phyllite, schist

Which of the following lists the rocks in the order of increasing grain size and increasing grade of metamorphism? a. schist, slate, phyllite b. slate, phyllite, schist c. phyllite, slate, schist d. slate, schist, phyllite

marble

Which of the following metamorphic rocks can be used to neutralize acidic mine waters? a. quartzite b. marble c. granitic gneiss d. slate

has abundant, coarse-grained mica

Which of the following statements concerning slate is not true? a. has abundant, coarse-grained mica b. rock cleavage is common c. sedimentary features may be visible d. forms from shales and mudstones

fault movements at shallow depths

Which of the following would exhibit sheared and mechanically fragmented rocks? a. intense compression in a deep-seated, regional metamorphic zone b. heating of shales and mudstones near a pluton c. fault movements at shallow depths d. regional metamorphism of pyroclastic volcanic rocks

quartzite

Word Analysis a. phyllite b. quartzite c. slate d. schist

melting

Word Analysis a. pressure b. recrystallization c. melting d. chemical fluids

melting

Word Analysis confining pressure differential stress melting chemical fluids

hornfels

________ is a nonfoliated rock formed by contact metamorphism of shale or mudstone a. schist b. hornfels c. marble d. gneiss

gneiss

________ is composed of alternating bands of light and dark silicate minerals. a. marble b. phyllite c. gneiss d. mica schist

granitic gneiss

_________ is characterized by the segregation of light and dark colored minerals into thin layers or bands a. slate b. garnet hornfels c. quartzite d. granitic gneiss

marble

__________ forms from the metamorphism of limestone or dolostone a. marble b. quartzite c. amphibolite d. migmatite

foliation

__________ is a strong parallel alignment of coarse mica flakes and/or of different mineral bands in a metamorphic rock a. marbleizing b. rock cleavage c. stress streaking d. foliation

quartzite

____________ is typically formed by metamorphism of a sandstone a. quartzite b. slate c. marble d. amphibolite

gneiss

coarse-grained metamorphic rock with alternating bands or stringers of light and dark minerals a. hornfels b. marble c. gneiss d. phyllite

schistose foliation

composed of larger minerals which are visible to the unaided eye, platy minerals tend to dominate

phyllitic foliation

composed of platy minerals that are slightly larger than those found in slaty cleavage, generally still to small to see with the unaided eye; large size gives the foliation a slightly shiny appearance

slaty cleavage

composed of platy minerals that are too small to see, typically split along parallel, planar surfaces

gneiss banding

easiest to recognize; composed of alternating bands of dark and light minerals

phyllite

foliated fine-grained metamorphic rock formed from mudstone and shale a. hornfels b. marble c. gneiss d. phyllite

hornfels

forms by contact metamorphism of mudstones and shales a. hornfels b. marble c. gneiss d. phyllite