chapter 7 metamorphism

Question 1

Thus, every metamorphic rock has a ______ —the rock from which it was formed

Answer 1

parent rock

Question 2

_______________, which means to “change form,”

Answer 2

Metamorphism

Question 3

Subducting sediments are metamorphosed due to __________________

Answer 3

increase in pressure and temperature

Question 4

Shallow crustal rocks are metamorphosed by ____________

Answer 4

heat from rising magma

Question 5

Deeply buried sedimentary strata are metamorphosed

Answer 5

burial metamorphism

Question 6

forces that deform rock that are unequal in different directions and are referred to as ______________

Answer 6

differential stress

Question 7

Pressure, like temperature, also increases with depth as the thickness of the overlying rock increases. Buried rocks are subjected to ____________, which is analogous to water pressure, in which the forces
are applied equally in all directions

Answer 7

confining pressure

Question 8

When substantial chemical change accompanies metamorphism the process is called _____________

Answer 8

metasomatism

Question 9

Recall that the term _______ is used to describe the size, shape, and arrangement of grains within a rock

Answer 9

texture

Question 10

The term _________ refers to any planar (nearly flat) arrangement of mineral grains or structural features within a rock

Answer 10

foliation

Question 11

__________ textures develop in a wide range of rock types and metamorphic environments when minerals in the parent rock recrystallize to form new minerals.

Answer 11

Porphyroblastic

Question 12

Notice that the dark biotite crystals and light silicate minerals (quartz and feldspar) have separated, giving the rock a banded appearance called ________ texture.

Answer 12

gneissic

Question 13

Under higher temperature- pressure regimes, the minute mica and chlorite crystals in slate begin to grow. When these platy minerals are large enough to be discernible with the unaided eye and exhibit a planar or layered structure, the rock is said to exhibit a type of foliation called ________

Answer 13

schistosity

Question 14

_______ no preferred directional texture

Answer 14

non-foliated texture

Question 15

Foliation can form in various ways, including:

Answer 15

-Rotation of platy and/or elongated minerals
-Recrystallization of minerals in the direction of preferred orientation
-Changing the shape of equidimensional grains into flattened or elongated shapes with preferred orientation

Question 16

_______ is a very fine-grained (less than 0.5 millimeter) foliated rock composed of minute mica flakes
that are too small to be visible

Answer 16

Slate

Question 17

________ represents a gradation in the degree of metamorphism between slate and schist. Its constituent platy minerals are
larger than those in slate but not yet large enough to be readily identifiable with the unaided eye

Answer 17

Phyllite

Question 18

________ is a coarse, crystalline metamor-
phic rock whose parent was limestone or dolostone

Answer 18

Marble

Question 19

_______ is a very hard metamorphic rock formed from sandstone , Under moderate- to high-grade metamorphism, the grains in sandstone fuse together.

Answer 19

Quartzite

Question 20

______________ occurs when rocks immediately surrounding a molten igneous body are “baked

Answer 20

Contact or thermal metamorphism

Question 21

When hot, ion-rich fluids circulate through fissures and cracks in rock, a chemical alteration called _________ occurs

Answer 21

hydrothermal metamorphism

Question 22

When the host rock is highly fractured, mineral matter contained in these _________ may precipitate to form a variety of minerals, some of which are economically important

Answer 22

hydrothermal solutions

Question 23

Most metamorphic rock is produced by ______________ during mountain building when large segments of Earth’s crust are intensely deformed along convergent plate boundaries

Answer 23

regional metamorphism

Question 24

Rocks and sediments can also be car- ried to great depths along convergent boundaries where oceanic lithosphere is being subducted. This phenomenon, called _________________, differs from burial metamorphism in that differential stresses play a major role in deforming rock as it is metamorphosed.

Answer 24

subduction zone metamorphism