Intro to rocks

Question 1

rock defintion

Answer 1

a coherent naturally occurring solid that’s consists of an aggregate of minerals or less commonly a body of glass

Question 2

define coherent

Answer 2

holds together on its own and must be broken in order to separate into smaller pieces

Question 3

do unnatached mineral grains consitute a rock

Answer 3

no

Question 4

Two main types of rocks

Answer 4

crystalline and clastic

Question 5

crystalline rock are

Answer 5

rocks whose grains interlock with one another like a puzzle

Question 6

granite (clast or cryst)

Answer 6

crystalline

Question 7

crystalline rocks grew

Answer 7

when an igneous melt solidified

Question 8

clastic rocks are

Answer 8

rocks that consist of separate grains that have been cemented together

Question 9

natural cement is composed of

Answer 9

minerals that have precipitated from water

Question 10

sandstone (clast or cryst)

Answer 10

clastic

Question 11

Grain vs crystal are _ when talking about rocks

Answer 11

interchangable

Question 12

grain defintion

Answer 12

mineral crystal in a rock or a fragment that has broken of either another rock or larger piece of mineral and has since almagamated forming another rock

Question 13

we will use the term crystal only when

Answer 13

referring to a piece of a single mineral that displays faces

Question 14

glass rock example

Answer 14

obsidian

Question 15

glass rock

Answer 15

either originated as a continuos mass or formed through the welding together of individual glass grains when they where still hot

Question 16

Three rock study scales

Answer 16

Hand sample
outcrop
thin section

Question 17

Hand sample

Answer 17

medium scale
what we do in labs

Question 18

outcrop

Answer 18

large scale
identifies basic rock types

Question 19

thin section

Answer 19

petrographic microscope
used to identify compostion

Question 20

High tech equipment is

Answer 20

more accurate but expensive

Question 21

2 forms of surface rocks

Answer 21

fragmented chunks
bedrock

Question 22

broken chunks or fragments are

Answer 22

pebbles cobbles or boulders
“clasts”
broken off bedrock by wind water ice or gravity
can be transported from source

Question 23

bedrock is

Answer 23

attached to the earths crust
surface exposure is outcrop
good for building on

Question 24

3 PRIMARY TYPES OF ROCKS

Answer 24

igneous
sedimentary
metamorphic

Question 25

igneous rocks form from

Answer 25

molten material

Question 26

two types of igneous (where they cooled) also third type

Answer 26

extrusive intrusive volcanic debris

Question 27

igneous etymology

Answer 27

latin ignis for fire

Question 28

sedimentary rocks are

Answer 28

loose classes that were broken off pre existing rock or by the precipitation of mineral crystals in water always formed at or near earths surface

Question 29

sedimentary rocks contain layers that

Answer 29

represent different periods of deposition and leave a detailed record of surface history

Question 30

metamorphic rocks from when

Answer 30

pre existing rocks change character in specific temperature pressure conditions

Question 31

metamorphic rocks can form from

Answer 31

sedimentary or igneous rocks

Question 32

metamorphic rocks form in what conditions

Answer 32

high temperature and pressure at extreme depth while still in solid state

Question 33

metamorphic rocks undergo chemical changes through

Answer 33

dissolution

Question 34

physical changes in metamorphic rocks include

Answer 34

squashing, stretching, or sheering

Question 35

define protolith

Answer 35

parent of a metamorphic rock

Question 36

upper temp limit to form metamorphic rocks

Answer 36

rock can not melt

Question 37

grades of metamorphic rock ranges from

Answer 37

high to low

Question 38

grains come in a wide range of

Answer 38

sizes

Question 39

equant grains are

Answer 39

same dimension in all directions (roughly ball shaped, but still could be angular)

Question 40

inequant grains are

Answer 40

not the same in all directions (look like poop)

Question 41

a grain can be a crystal or a

Answer 41

clast

Question 42

composition refers to

Answer 42

the proportions of different chemicals that make up a rock

Question 43

chemical composition alone

Answer 43

does not control the assemblage of minerals in a rock

Question 44

texture refers to

Answer 44

the configuration of grains in a rock

Question 45

texture relies on

Answer 45

composition and grain shape

Question 46

igneous textures include

Answer 46

crystalline, fragmental, glassy

Question 47

layers in sedimentary rocks is

Answer 47

bedding

Question 48

layers in metamorhpic rocks is

Answer 48

foliation

Question 49

bedding is

Answer 49

separate layers of deposition over time

Question 50

foliation is

Answer 50

the arrangement of minerals in the rock brought on by physical and chemical changes

Question 51

the rock cycle is

Answer 51

the progressive transformation of earth materials from one rock type to another over time

Question 52

sedimentary goes to metamorphic through

Answer 52

burial and heating

Question 53

metamorphic goes to igneous by

Answer 53

melting

Question 54

igneous goes to sedimentary by

Answer 54

erosion transportation and deposition

Question 55

sedimentary goes to igneous by

Answer 55

heating and melting

Question 56

metamorphic goes to sedimentary by

Answer 56

erosion ,transportation and deposition

Question 57

igneous goes to metamorphic by

Answer 57

burial and or heating

Question 58

sedimentary goes to sedimentary by

Answer 58

erosion, transportation and redeposition

Question 59

metamorphic goes to metamorphic by

Answer 59

burial heating and remetamorphism

Question 60

igneous got to igneous by

Answer 60

heating and remelting

Question 61

new melt enters crust from the

Answer 61

mantle

Question 62

material returns to the mantle by

Answer 62

subduction