Exam One V Flashcards Preview

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Flashcards in Exam One V Deck (14):
1

______ is the age of a geologic event or feature compared to other geologic events or features:

Relative Age

2

_____ is the age in years of a particular geologic event or feature, generally obtained with radiometric dating techniques:

Absolute Age

3

In stratigraphy, a member is _____

a minor unit within a formation

4

_________ is the matching of sedimentary rocks of similar ages in different regions:

Correlation

5

A ______ is a rock unit that is distinctive enough in appearance that a geologic mapper can tell it apart from the surrounding rock layers:

Formation

6

_____ are life forms which existed during limited periods of geologic time and thus used as guides to the age of the rocks in which they are preserved:

Index Fossils

7

Which of the characteristics below is indicative of a good index fossil?

Geographically widespread

8

Fossils in sedimentary rock strata succeed each other vertically in a specific, reliable order:

Principle of Faunal Succession

9

________ determined that the exact time the Earth formed was 4004 BC:

James Usser

10

_________ discovered radioactivity in 1896

Henri Becquerel

11

______ was the first person to propose that radioactive elements can be used to absolutely age-date rocks:

Ernest Rutherford

12

_______ determined Earth's age to be between 80-100 Ma based on amount of time it took for fresh ocean water to become salty:

John Jolly

13

Radioactive age-dating is usually not performed on _____ rocks:

detrital sedimentary

14

______ is the amount of time it takes for half of the radioactive nuclei in an unstable element to change to a stable element

Half life