Lesson 1 - Ocean Formation Flashcards
What percentage of the Earth’s surface is covered by the ocean?
70%
What geological processes take millions of years in the ocean?
Formation and destruction of ocean basins
How long ago did Earth and our solar system probably form?
Approximately 4,550 billion years ago
What caused the initial formation of Earth and the solar system?
Clouds of stellar dust and gas condensed from the debris of a supernova explosion
What is a supernova explosion?
When a dying star collapsed then exploded, sending massive quantities of dust and gas into space
What are planetesimals?
Small planets formed from larger particles, around 10km in diameter
What are the small rocky inner planets of our solar system?
- Mercury
- Venus
- Earth
- Mars
What are the large gaseous outer planets of our solar system?
- Jupiter
- Saturn
- Uranus
- Neptune
- Pluto
What happened to lighter elements during the formation of the planets?
They were blasted out into space or contributed to the larger gaseous outer planets
Where did the heavier elements settle during the formation of the solar system?
Closer to the Sun, incorporated into the rocky planets
What caused heating of the Earth during its early bombardment?
Frictional energy and radioactive decay of heavy elements
What heavy elements settled toward the core of the Earth?
Iron and nickel
What are the four main layers of the Earth’s interior?
- Upper Mantle
- Lower Mantle
- Outer Core
- Inner Core
Is continental crust thicker or thinner than oceanic crust?
Thicker
What causes volcanic activity within the Earth’s mantle?
Radioactive decay and heat convection
What is the composition of the mantle beneath the crust?
Viscous rock
What do volcanic vents release to the surface?
Hot magma and gases
What process formed the early atmosphere of the Earth?
Gases from volcanic activity
What developed due to the presence of water vapor in volcanic gases?
A cycle of rainfall and evaporation
What formed primitive shallow seas on Earth?
Water collecting in depressions on the surface
What factors contributed to the composition of early seawater?
- Atmospheric gases
- Chemicals dissolved from rocks
What is the diameter of Earth across the Equator?
12,756 km
What is the average distance of Earth from the Sun?
150 million km
