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Flashcards in Relative Age Deck (49)
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1

What are two schools of thought about how old the earth is?

Catastrophism, Uniformitarianism

2

In the field of thought called ________ people thought that large-scale geologic features formed in catastrophic events

catastrophism

3

What two ideas did Catastophists believe about the Earth/

1. large-scale geologic features formed in catastrophic events

2. the age of Earth was measurable in human historical terms

4

which field of thought is accepted by much of the scientific community?

uniformitarianism

5

Uniformitarianism says that past and present _____ processes are similar

geologic

6

Uniformitarianism says that...

past and present geologic processes are similar

7

This field of thought says that past and present geologic processes are similar?

uniformitarianism

8

When we say that past and present geologic processes are similar, we mean that...

we can look at geologic processes that are occurring today and backtrack and assume that they are similar to the processes that have operated throughout earths history

9

Since today we don't see large-scale catastrophes occurring not the face of he earth, what can we assume?

we can assume that these did not happen in Earth's past either, rather its the thought that Earth's processes move more slowly and the earth is much much older than the span of human history

10

Do Earth's processes move slow of fast?

slow

11

what does uniformitarianism propose?

Earth was ancient much beyond the span of human history

12

What is relative age?

looking at two different things and broadly comparing there ages.

13

Relative age is looking at two different things and _______ there ages

comparing

14

when determine the relative age of two different things do we find the precise number or age of them?

NO

We determine which events happened first, second, third, etc.

15

Stratigraphy is...

the science of looking at different layers of rocks the processes that form those layers

the science of rock layers and strata-forming processes

16

Stratigraphy is the science of _____ layers and strata-forming ______

rock, processes

17

There are a couple different ______ developed through stratigraphy laws that help us to determine the relative age of rock layers

laws

18

What does the law of original horizontality say?

sedimentary beds or strata laid in water are laid horizontally.

19

This law says that sedimentary beds or strata laid in water are laid horizontally.

law of original horizontality

20

The law of original horizontality says that sedimentary beds or strata laid in water are laid ________

horizontally

21

when sediment is deposited at the bottom a lake, the sediment accumulates in _________ layers

horizontal

22

The law of original horizontality applies mostly to...

sedimentary rocks

23

If you see layer that are angled or curved, there must have been some ______ that ______ those layers from their original deposition

event, altered

24

Under the law of original horizontality, what can we infer from observing an angled or curved sedimentary layer?

there has been some event that altered those layers from their original deposition

25

What does the principle of superposition state?

that in undisturbed strata or layers, younger layers are deposited above older ones.

26

The principle of superposition states that in undisturbed strata or layers, _______ layers are deposited above ______ ones.

younger, older

27

which principle/law states that in undisturbed strata or layers, younger layers are deposited above older ones?

law of superposition

28

What does the principle of cross-cutting relationships state?

that any feature cutting through or disrupting a layer is younger than the layer itself.

29

What does the principle of cross cutting relationships mainly apply too?

faults and dikes

30

a fault must be younger then the layers of rock because the layers of rock had to have been deposited _______ in order for the fault to displace them

first