Chapter 2

Question 1

What is the Age of the Universe?

Answer 1

4.567 Billion Years

Question 2

What is the Age of the Earth?

Answer 2

4.54 Billion Years

Question 3

What is the oldest mineral age?

Answer 3

4.404 Billion Years

Question 4

When is Theia crash into earth?

Answer 4

4.48 Billion years ago

Question 5

What are the three principles that form the basis of all geological mapping?

Answer 5

1. Sedimentary rock layers are deposited on top of eachother 2.Layers are lying flat when they are deposited 3.Layers are deposited over large areas

Question 6

What is the Priciple of Superposition?

Answer 6

Layers of rock below other layers of rock are the younger rocks.

Question 7

What is the Principle of Original Horizontality?

Answer 7

All sedimentary strata begins by lying flat (horizontal).

Question 8

What is the principle of Original Laterla Continuity?

Answer 8

Flat lying sedimentary strata begins by lying in all directions ( therefore slanted strata must have experienced some stress to have moved them)

Question 9

What is an unconformity?

Answer 9

horizons in rock that represent a time break during which erosion of a sequence of rock took place prior to the deposition of a more recent time sequence.

Question 10

What is an angular unconformity?

Answer 10

An unconformity where horizontally parallel strata are deposited on titled and eroded layers producing an angular discordance with the overlying horizontal layers

Question 11

What is a disconformity?

Answer 11

An unconformity between parallel layers of sedimentary rocks which represents a period of erosion and non-deposition.

Question 12

What is a non-conformity?

Answer 12

A non-conformity exists between sedimentary rocks and metamorphic or igneous rocks when the sedimentary rock lies above and was deposited on the pre-existing and eroded metamorphic or igneous rock.

Question 13

What is the Principle of Cross-Cutting Relationships?

Answer 13

This does three things: 1. A fault is younger than the youngest rock it cuts. 2. the strata above an unconformity are younger than the strata below 3. any feature that cuts across a rock must be younger than the rock it cuts

Question 14

What is the Principle of Faunal Succession? Who first found the reasons for this principle?

Answer 14

The age of rock layers based on the fossils found in them, which was similar across multiple geographies, found by canal engineer William Smith.

Question 15

What are “Eras”?

Answer 15

Long intervals of geologic time separated by major extinction events.

Question 16

Who discovered that atoms of some chemical elements are inherently unstable and breakdown?

Answer 16

Henri Bequerel

Question 17

What does the atomic number of an element represent?

Answer 17

The number of protons in the nucleus.

Question 18

What does the Atomic Mass of an element represent?

Answer 18

The number of protons plus the number of neutrons.

Question 19

What are isotopes?

Answer 19

Atoms of the same element that differ in their number of neutrons in the nucleus?

Question 20

What are the three described ways in which an isotope can decay?

Answer 20

1.either a proton or a neutron will turn into the other. 2. Two Neutrons and two protons bound tightly together eject from the element (alpha particle) 3. Fission: a neutron CRASHES into a nucleus and make it break into two smaller particles with different weights

Question 21

What is the parent and daughter in the case of radioactive decay?

Answer 21

Parent = original, daughter = new isotope

Question 22

What is a half-life?

Answer 22

The period of time in which exactly half of the nuclei of a species of radioactive substance would decay

Question 23

Describe the process where we date organic matter?

Answer 23

A process called carbon dating where we use Carbon 14 and Carbon 12(the latter does not decay), carbon 14 is radiactive and has a half life of 5730 years, thus allowing us to date organic matter up to 50,000 years back.