Lesson 4 - Rocks

Question 1

this rock is formed from the solidification of molten material (magma or lava)

Answer 1

igneous rocks

Question 2

naturally occurring solid mixture of one or more minerals, or organic matter

Answer 2

rocks

Question 3

how are rocks classified?

Answer 3

• how they are formed
• composition
• texture

Question 4

two types of igneous rocks:

Answer 4

1. intrusive igneous rocks
2. extrusive igneous rocks

Question 5

formed from solidified magma underneath the earth

Answer 5

intrusive igneous rocks

Question 6

gradual lowering of the temperature gradient at depth towards the surface would cause slow cooling/crystallization

Answer 6

intrusive igneous rocks

Question 7

this type of rock has phaneritic texture

Answer 7

intrusive igneous rocks

Question 8

compromised of large crystals that are visible to the eye

Answer 8

phaneritic texture

Question 9

formed from solidified lava at or near the surface of the earth

Answer 9

extrusive igneous rocks

Question 10

common textures of extrusive igneous rocks?

Answer 10

• aphanitic
• porphyritic
• vesicular

Question 11

igneous rocks based on their texture and mineral composition:

Answer 11

• felsic
• intermediate
• mafic
• ultramafic

Question 12

also called granitic; >65% silica, generally light-colored

Answer 12

felsic

Question 13

also called andesitic; 55-65% silica; generally medium colored (medium gray)

Answer 13

intermediate

Question 14

also called basaltic; 45-55% silica; generally dark colored

Answer 14

mafic

Question 15

<45% silica; generally, very dark colored; composed
mainly of olivine and pyroxene which are the major constituents of the upper mantle

Answer 15

ultramafic

Question 16

these are rocks that formed through the accumulation, compaction, and cementation
of sediments

Answer 16

sedimentary rocks

Question 17

two types of sedimentary rocks:

Answer 17

1. clastic sedimentary rocks
2. non-clastic sedimentary rocks

Question 18

formed from the accumulation and lithification of sediments derived from the breakdown of pre-existing
rocks

Answer 18

clastic sedimentary rocks

Question 19

derived from sediments that precipitated from concentrated solutions or from the accumulation of biologic or organic material

Answer 19

non-clastic sedimentary rocks

Question 20

two types of non-clastic sedimentary rocks:

Answer 20

1. chemical sedimentary
2. organic sedimentary

Question 21

minerals crystallize out of solution to become rock

Answer 21

chemical sedimentary

Question 22

gypsum and halite is what type of rock?

Answer 22

sedimentary rocks, non-clastic (chemical sedimentary)

Question 23

remains of plants and animals

Answer 23

organic sedimentary

Question 24

rocks that are formed from the transformation of pre-existing rocks

Answer 24

metamorphic rocks

Question 25

this process involves changes in the physical and chemical properties of rocks in response to heat, pressure, and chemically active fluids

Answer 25

metamorphism

Question 26

two types of metamorphism:

Answer 26

• contact metamorphism
• regional metamorphism

Question 27

heat as the main factor: occurs when a pre-existing rocks get in contact with a heat source (magma)

Answer 27

contact metamorphism

Question 28

hornfels is what type of rock?

Answer 28

metamorphic rock, contact metamorphism

Question 29

fine-grained non-foliated metamorphic rock produced by contact metamorphism

Answer 29

hornfels

Question 30

pressure as main factor, it occurs in areas that have undergone deformation during orogenic event resulting in mountain belts

Answer 30

regional metamorphism

Question 31

schist and gneiss is what type of rock?

Answer 31

metamorphic, regional metamorphism