C4.1 The Earth and its atmosphere Flashcards
In order, what are the four layers that make up the Earth?
- The outer layer is the rocky crust. It is between 8km and 40km thick.
- Beneath the crust is the mantle. This is made of solid rock, but it can flow very slowly. Very slowly, hotter rock rises and cooler rock sinks.
- About halfway to the centre of the Earth is the core. This is mainly iron and nickel. The outer core is liquid, and the inner core is solid.
How can scientists learn about the Earth’s structure?
Scientists can learn about the Earth’s structure by studying shock waves from earthquakes. They also examine rocks from the surface and under oceans; and also materials that volcanoes bring to the surface.
What are the six most common elements in the Earth’s crust?
The six most common elements in the Earth’s crust are:
Oxygen Silicon Aluminium Iron Calcium Sodium
What is the atmosphere?
The atmosphere is a mixture of gases that surrounds the Earth.
What is the part of the atmosphere nearest the Earth called?
The part of the atmosphere nearest the Earth is called the troposphere.
What is the troposphere?
The troposphere is the part of the atmosphere nearest the Earth.
What is the troposphere mainly made of?
The troposphere is mainly a mixture of two elements: nitrogen and oxygen. There are small amounts of other substances including argon and CO2.
What are the gases that make up the Earth’s atmosphere? Give the percentages.
Nitrogen -> 78%
Oxygen -> 21%
CO2 -> 0.04%
Other gases (including water vapour and argon) -> 1%
What two elements does the core mainly consist of?
The core mainly consists of iron and nickel.
What is the crust?
The crust is the rocky outer layer of the Earth.
What is the mantle?
The mantle is the layer of Earth that is below the crust..
It is solid but it can flow very slowly.
What is the outer core?
The outer core is liquid iron and nickel between the Earth’s mantle and inner core.
What is the inner core?
The inner core is the solid iron and nickel in the centre of the Earth.
