Geography: Volcanoes and Earthquakes.

What is a fault?

A crack in the earths crust.

What is an earthquake?

An earthquake is a sudden movement in the earths crust that occurs along a fault, or crack in the rock.

How are conventional currents created?

Convectional currents are created by the heat of the earths core.

What is a collision boundary?

A collision boundary is when the plate boundaries go towards each other but they don't go underneath one another. This causes an earthquake.

What is a conservative/ sliding boundary?

A conservative boundary is when the plate boundaries rub against each other causing an earthquake.

What is a constructive/ divergent boundary?

A constructive boundary is when the plate boundaries are going apart from each other and it creates volcanoes.

What is a destructive boundary (convergent boundary)

A destructive boundaries is when plate boundaries are going towards each other and one of the plate boundaries go underneath the other. This causes earthquakes and volcanoes.

What is an seismic wave?

A shock wave, or vibration, from an earthquake.

What is an volcano?

A volcano is an opening in the earths crust where magma, molten rock deep below ground comes to the surface as lava.

What is the ring of fire?

About 80%of the worlds major earthquakes and volcanoes are found around the ring of fire.

What is continental drift?

Continental drift is when plates move.

Tell me about continental plates.

Continental plates make up the continental land masses we live on. They are thicker, older and from less dense rock than oceanic plates. Example: Eurasia plate.

What is lava?

Lava is molten rock produced by volcanoes.

Tell me about the oceanic plates.

Oceanic plates line our country floor. They are thinner, newer and made from more dense rock than continental plates. Example: nazca plate.

What are seismic waves?

Seismic waves are vibrations from earthquakes and can measure how the waves travel through the earth.

How are tectonic plates created?

Tectonic plates are created when the earths crust is broken into enormous segments (which are tectonic plates)

Tell me about the continental crust.

The continental crust forms 1/3 of the earths surface and forms all major continents.It is up to 65km (including the highest mountains) and is old, less dense (lighter)and difficult to be destroyed. It is mainly made up of granite.

What is the crust?

The crust is 10-65 km thick and the crust is thinnest under the oceans and thickest where there are mountains.

What's the worlds deepest ocean and facts about it.

The deepest ocean at is the Pacific Ocean at 10, 994 m.

What's the worlds highest mountain and facts about it.

The highest mountain is Mount Everest at 8,848 m.It's location is in Nepal and is apart of the Himalayas.

What is the inner core?

The inner core is the hottest layer and is 2000 km thick . The inner core is a centre of solid, dense rock made of iron and nickel.

What is a plate boundary

The line where 2 plates meet is a plate boundary. This is where most of the earths earthquakes and volcanoes occur.

What is the mantle?

The mantle is the widest layer of earth (2900 km thick) consisting of semi-molten rock known as magma, which appears on the surface through volcanoes as lava.

Tell me about the oceanic crust..

The oceanic crust forms 2/3s of the earths surface and underlies most major oceans. It is about 10 km thick and rarely rises above the surface of the ocean. It is denser (heavier)and is always destroyed and replaced at plate boundaries. It is also made up of basalt.

What is the Outer Core?

The outer core is 1300 km thick and is molten due to immense heat and pressure.

What is an epicentre?

The point of the surface above the origin of an earthquake.

What is a focus?

The point, underground, where an earthquake originates.

What do the plates float like on top of the mantle ?

The tectonic plates move like rafts on top of the mantle.

What is the Richter scale?

This is the scale used to measure the strength if earthquakes. It goes on a scale of 1-10. Geologists measure the magnitude, the strength of an earthquake with an instrument called a seismometer that picks up seismic waves.