Chapter 8 E2

Question 1

father of modern geology

Answer 1

James Hutton, Theory of the Earth

Question 2

James Hutton came up with the fundamental principle of geology that says

Answer 2

the present is the key to the past; uniformitarianism

Question 3

determining when a geologic feature formed relative to other geologic features

Answer 3

relative age

Question 4

determining when a geologic event occurred in exact units of time

Answer 4

radiometric or absolute age

Question 5

law of superposition

Answer 5

oldest rocks are on the bottom

Question 6

principle of original horizontality

Answer 6

sediment is deposited horizontally

Question 7

principle of cross-cutting relationships

Answer 7

younger feature cuts through an older feature

Question 8

one rock contained within another rock

Answer 8

inclusions

Question 9

the rock containing the inclusions is

Answer 9

younger

Question 10

a break in the rock rock record

Answer 10

unconformity

Question 11

three types of unconformities

Answer 11

disconformity, angular unconformity, and nonconformity

Question 12

missing time between horizontal SEDIMENTARY layers

Answer 12

disconformity

Question 13

missing time between two sets of strata that are not parallel to each other

Answer 13

angular unconformity

Question 14

unconformity between igneous or metamorphic rocks and younger sedimentary rocks

Answer 14

nonconformity

Question 15

local unconformity

Answer 15

forms when a different rock unit is deposited within another relatively continuously deposited rock unit; find them in CHATANOOGA on the ancient river channel

Question 16

matching rocks of similar age in different regions; often relies on fossils

Answer 16

correlation of rock layers

Question 17

cavities and pores are filled with precipitated mineral matter

Answer 17

petrified fossils

Question 18

cell material is removed and replaced with mineral matter

Answer 18

replacement

Question 19

shell or other structure is buried and then dissolved by underground water

Answer 19

mold

Question 20

hollow space of a mold is filled with mineral matter

Answer 20

cast

Question 21

organic matter becomes a thin residue of carbon

Answer 21

carbonization

Question 22

replica of the fossil’s surface preserved in fine grained sediment

Answer 22

impression

Question 23

hardened resin of ancient trees surrounds an organism

Answer 23

preservation in amber

Question 24

conditions favoring fossil preservation

Answer 24

rapid burial and possession of hard parts

Question 25

______ fossils allow various sedimentary layers around the world to be correlated

Answer 25

index

Question 26

variant of the same parent atom; different number of neutrons and mass number

Answer 26

isotope

Question 27

spontaneous breaking apart (decay) of atomic nuclei

Answer 27

radioactivity

Question 28

three types of radioactive decay

Answer 28

alpha emission, beta emission, and electron capture

Question 29

lose an alpha particle

Answer 29

alpha emission

Question 30

lose an electron

Answer 30

beta emission

Question 31

gain an electron that changes into a neutron?

Answer 31

electron capture

Question 32

the time for one half of a radioactive nuclei to decay

Answer 32

half life

Question 33

carbon 14 is used for dating ____ events

Answer 33

recent

Question 34

divisions of the geological calendar from biggest to smallest

Answer 34

eon
era
period
epoch

Question 35

the era that is 88% of Earth’s history

Answer 35

precambrian era