How the Earth was Made

Question 1

According to Archbishop Usher, the Earth was ___ years old.

Answer 1

6000 years old.

Question 2

Who was James Hutton? How did he determine that the Earth was far older than once believed?

Answer 2

He was a Scottish farmer interested in Geology. He was also known as the Father of Modern Geology. He discovered ancient rock that he concluded had formed millions of years ago.

Question 3

Describe the Earth during its first million years. Where did the material come from to build the early Earth?

Answer 3

There were oceans of molten rock which stretched miles deep. The material came from meteors.

Question 4

Lord Kelvin calculated the Earth’s age to be about ______ years old.

Answer 4

20 million years.

Question 5

Why was Lord Kelvin’s calculation so far off from Earth’s actual age?

Answer 5

He didn’t consider the radioactive elements present on the Earth that were preventing it from cooling.

Question 6

Describe how radioactive dating works.

Answer 6

The radioactive element Uranium decays into lead. By measuring the ratio of uranium to lead in the crystals trapped in the ancient rocks, one could calculate the age of the rock.

Question 7

The currently accepted age of the Earth is _______ years.

Answer 7

4.5 billion years.

Question 8

What do pillow lavas tell us about Earth’s history?

Answer 8

The presence of pillow lavas, confirms the presence of large bodies of water on the Earth’s surface, early in Earth’s history.

Question 9

What are two likely sources of the Earth’s early water?

Answer 9

The two most likely sources of water on early Earth were asteroids and comets.

Question 10

Describe the Earth’s early ocean and atmosphere.

Answer 10

The oceans were green because they were rich in iron and thick clouds of carbon dioxide and water vapor enveloped the Earth.

Question 11

Describe the first land masses to appear on Earth.

Answer 11

Small volcanic islands.

Question 12

How were the first granite rocks formed?

Answer 12

Underwater volcanic eruptions created a fractured crust. Water plunged alongside molten lavas. Mixture of super-heated water and basaltic lava gave rise to granite.

Question 13

In what ways is granite different from basalt? Describe three differences between the two.

Answer 13

1. Granite is lighter than basalt as it is less dense
2. Granite is tougher than basalt,
3. Granite forms beneath the surface and basalt forms at the surface.

Question 14

Granite rocks formed the corps of Earth’s first _____

Answer 14

continents.

Question 15

What are stromatolites, and how did they affect the environment of Earth?

Answer 15

They are mounds of thin layers of cyanobacteria capable of photosynthesis. These were the first living organisms that added oxygen to the environment.

Question 16

How did the change in Earth’s atmosphere affect the appearance of the planet?

Answer 16

The atmospheric oxygen dissolved in the oceans and rusted the iron. As the iron left the ocean, the green oceans turned blue and the atmosphere cleared up as well.

Question 17

Sediments from this period formed the source of most of the _____ that humans use today.

Answer 17

Iron

Question 18

What is meant by the fossil paradox?

Answer 18

Fossils showing intercontinental distribution.

Question 19

What was Alfred Wegener’s radical proposal?

Answer 19

The continents had been joined together and then had later drifted apart (Continental Drift).

Question 20

What did the U.S. Navy discover when they mapped the ocean floor?

Answer 20

Tectonic Plates

Question 21

Continents move at the rate of _____ per year.

Answer 21

2.5 cm per year.

Question 22

Describe Rodinia.

Answer 22

It was a supercontinent with the US and Canada at the heart of the landmass. It was desolate and lifeless.

Question 23

How did the formation of Rodinia affect the Earth’s environment and its life forms?

Answer 23

The land was barren and desolate. The oceans were teeming with primitive life forms.

Question 24

Describe conditions on Earth 650 million years ago.

Answer 24

Earth was covered in deep ice.

Question 25

Describe what took place between 630 and 550 million years ago?

Answer 25

Rodinia broke into tiny fragments and ice no longer covered the Earth.

Question 26

The “Cambrian Explosion” of new life forms was made possible by high levels of _____ in the Earth’s atmosphere

Answer 26

oxygen

Question 27

What did the fossils in the Burgess Shale reveal about the Earth’s past?

Answer 27

Diverse forms of life appeared 500 million years ago.

Question 28

How did the formation of an ozone layer allow life forms to develop on land?

Answer 28

Life from the ocean could move from the ocean to land as the ozone layer acted as a UV shield protecting the animals.

Question 29

Describe the conditions on the surface of Earth’s continents during the Carboniferous Period, 300 million years ago.

Answer 29

Swampland, large plants, forest canopies, jungles.

Question 30

Which period did most of our coal and gas come from?

Answer 30

Much of the Earth’s present-day supply of coal and gas was formed during the Carboniferous Period.

Question 31

What kinds of animals appeared during the Carboniferous Period?

Answer 31

Enormous insects, amphibians, early reptiles.

Question 32

What happened in Siberia 250 million years ago? How did this affect lifeforms on earth?

Answer 32

Volcanic eruptions leading to a mass extinction event. 95% of lifeforms were driven to extinction.

Question 33

The supercontinent ____ formed 250 million years ago.

Answer 33

Pangea

Question 34

Why were dinosaurs able to grow so large?

Answer 34

Because of the oxygen rich environment and because they were not cold blooded.

Question 35

What began to happen 180 million years ago?

Answer 35

Volcanic eruptions split apart Pangea and created the modern day continents.

Question 36

How did the increase in carbon dioxide concentrations in the atmosphere affect Earth’s environments?

Answer 36

The global temperature increased, which created tropical forests, which led to more diversity and therefore more food for the dinosaurs (that is how they became enormous).

Question 37

Where do diamonds come from?

Answer 37

From volcanism. Extreme pressure and high temperatures deep inside the volcano forms diamonds that are then brought up to the surface through eruptions.

Question 38

The thin layer of clay (“Tombstone Layer”)that was formed at the time of the dinosaur’s extinction contains the rare element ______.

Answer 38

Iridium.

Question 39

Describe the two catastrophic events that occurred 65 million years ago.

Answer 39

A meteor hit our planet and a massive volcanic eruption happened in India.

Question 40

The Swiss Alps resulted from the collision between the ____ continent and the _______ continent.

Answer 40

The African continent and the European continent.

Question 41

What caused the planet to cool down during the ice age?

Answer 41

The ice ages had arrived caused by volcanic eruptions that created a land bridge connecting North and South America. This cooled down the oceans and resulted in the ice ages.

Question 42

Describe the evidence that glaciers once covered New York City.

Answer 42

The outcrops in Central Park bear the imprints of an Ice Age.

Question 43

What do geologists predict will occur 200 million years from now a now?

Answer 43

A Supercontinent called Pangea Ultima will be formed, and North America will collide with Africa.