test geologic time, met rocks

Question 0

Daughter product

Answer 0

The product of radioactive decay of a parent isotope

Question 1

Absolute age

Answer 1

The actual age of a material in years

Question 2

Parent isotope

Answer 2

An unstable isotope that will undergo radioactive decay

Question 3

Half life

Answer 3

The amount of time required for half of the unstable parent substance to decay to the daughter product

HOW YOU FIND AGE OF ROCK

Question 4

Radiometric dating

Answer 4

ratio between daughter and parent to find absolute age of rock

Question 5

Radioactivity

Answer 5

Emission of high energy particles by unstable isotopes

Question 6

geologic time scale

Answer 6

divides history of earth into time intervals

Question 7

divisions of time

Answer 7

eon–> era—> period–> epoch–> year

Question 8

age of earth

Answer 8

4.6 by

Question 9

human existence vs. earth’s

Answer 9

humans= so small compared to earth’s like a sliver

Question 10

uniformitarianism

Answer 10

present is key to the past

Question 11

principle of original horizontality

Answer 11

sedimentary strata always form in horizontal layers

Question 12

principle of original superposition

Answer 12

oldest layer of rock is on the bottom

Question 13

law of cross cutting relationships

Answer 13

rock unit that crosses over another unit is always younger

Question 14

principle of inclusions

Answer 14

inclusions are always older than the rock they are inside of

Question 15

intrusions- young or old

Answer 15

always younger than rock they cut into

LOOK FOR FINGERS WHEN FINDING INTRUSIONS

Question 16

disconformity

Answer 16

sed layers that have been eroded away, then covered by other depositing layers

Question 17

nonconformity

Answer 17

erosional surface w igneous/metamorphic rock below, sed rock above

stratified rock rests on un stratified (igneous) rock

Question 18

angular unconformity

Answer 18

angled or folded sed rocks are located below the erosional surface and horizontal layers of sed rocks are above

sed layers that have been tilted by force of tectonic plates then eroded

Question 19

foliation

Answer 19

rock its layered, almost has skins peeling off, sheet like

when pressure squeezes flat minerals so they become aligned

Question 20

protolith

Answer 20

first rock

Question 21

regional metamorphism

Answer 21

large scale folding by compression at subduction zones

produces foliated rocks

Question 22

contact metamorphism

Answer 22

when magma comes into contact with an already existing body of rock- usually sed
produces non foliated rocks

Question 23

foliated rock

Answer 23

heat and pressure
subduction zones
regional metamorphism

Question 24

non-foliated rock

Answer 24

heat igneous intrusion contact metamorphism

Question 25

baked zone

Answer 25

in contact metamorphism, when igneous intrusion happens- rock that is affected

Question 26

dike

Answer 26

vertical intrusion

Question 27

sill

Answer 27

horizontal intrusion

Question 28

metamorphic rock

Answer 28

come from other existing rocks when heat/pressure changes the mineral content changes (while solid) into minerals that are stable at different temperatures and different pressures IF IT MELTS ITS NOT METAMORPHIC

Question 29

igneous rock

Answer 29

come from cooled magma

Question 30

sedimentary rocks

Answer 30

come from layered sediments

Question 31

sediments

Answer 31

broken rock fragments, can vary in size, shape, density

Question 32

magma

Answer 32

hot liquid that comes from within the earth's crust | forms igneous rock

Question 33

heat/pressure

Answer 33

subduction zones hot pressure from crashing plates

Question 34

deposition

Answer 34

settling of sediments in water, layering

Question 35

compaction

Answer 35

flattening of layers due to overlying sediments

Question 36

cementation

Answer 36

gluing together of the sediments w calcite and silica

Question 37

weathering

Answer 37

breaking down existing rocks into sediments

Question 38

erosion

Answer 38

transportation of sediments by four forces

Question 39

WHEN SEQUENCING ROCKS

Answer 39

start at oldest unit at the bottom

Question 40

folds in rock (ripple things) are a

Answer 40

sign of metamorphism

Question 41

magma chamber

Answer 41

large mass of magma that has solidified- may cause surrounding rocks to melt/metamorphose