Absolute dating and relative dating test

Question 1

What is absolute dating?

Answer 1

Using radioactive atoms to find the ages of rock layers and fossils.

Question 2

What is relative dating

Answer 2

Any method of measuring the age of an event or object

Question 3

Atomic number

Answer 3

number of protons in an atom

Question 4

Mass number

Answer 4

number of protons plus neutrons

Question 5

Isotope

Answer 5

atoms of the same element that have different number of neutrons

Question 6

daughter atom

Answer 6

the stable form of an element

Question 7

parent atom

Answer 7

the unstable element

Question 8

what is radioactivity

Answer 8

process of decay (unstable to stable)

Question 9

what is half-life?

Answer 9

one half of a sample of unstable isotopes will become stable

Question 10

Name three radioactive substances that are used in radiometric dating.

Answer 10

Carbon 14-once living things, Potassium-Argon- rocks older than 100,000 years, Uranium-Lead-rocks older than 10 million years old; Rubidium-Strontium- rocks older than 10 million years

Question 11

What are one pro and one con for using carbon 14 for radiometric dating?

Answer 11

Pro - Can be used on anything that was once living.

Con- Has a limit of only 50,000 years due to a relatively short half-life.

Question 12

What is Uniformitarianism and give an example? Who came up with the theory?

Answer 12

Processes that shape the earth, like erosion and deposition, remain the same over time. James Hutton

Question 13

What is Catastrophism and give an example?

Answer 13

The earth changes due to drastic and sudden events like meteor impacts, volcanoes, earthquakes, and tsunamis.

Question 14

What is the principal of superposition?

Answer 14

Oldest rock layers lie beneath younger rock layers in undisturbed rock layers.

Question 15

What is the geologic column?

Answer 15

An idealized sequence of rock layers that contains all the known fossils and rock formations on earth, arranged from oldest to youngest.

Question 16

What is horizontal origin and cross cutting?

Answer 16

Horizontal origin states that most rock layers form in horizontal bands and if the rocks are arranged in any other way then there had to be some force that acted on the rocks. Cross cutting states that a fault or igneous intrusion is younger than the rocks the cut across.

Question 17

What are unconformities?

Answer 17

Missing rock layers that cause a break in the sequence of rock layers.

Question 18

Name and describe three types of unconformities.

Answer 18

Disconformity-most common, a missing sequence in parallel rock layers; Nonconformity- older sedimentary rock layers lie on top of eroded igneous or metamorphic rock; Angular unconformity- found between horizontal layers of sedimentary rock and layers that have been tilted or folded.