Earthquakes are caused by the release of built-up pressure inside the Earth's crust. An earthquake's power is measured on the Richter scaleusing an instrument called a 'seismometer'.An earthquake is the shaking and vibration of the Earth's crust due to movement of the Earth's plates (plate tectonics). Earthquakes can happen along any type of plate boundary
- short-term (immediate) impacts
- long-term impacts
- social impacts (the impact on people)
- economic impacts (the impact on the wealth of an area)
- environmental impacts (the impact on the landscape)
MEDC= A more economically developed country
LEDC= A less economically developed country
Volcanoes and Plate Boundary
Different plate boundaries
- At a tensional, constructive or divergent boundary the plates move apart.
- At a compressional, destructive or convergent boundary the plates move towards each other.
- At a conservative or transform boundary the plates slide past each other.
- A volcano is formed by eruptions of lava and ash.
- Volcanoes are usually cone shaped mountains or hills.
- When magma reaches the Earth's surface it is called lava. When the lava cools, it forms rock.
- Volcanic eruptions can happen at destructive and constructive boundaries, but not at conservative boundaries.
- Some volcanoes happen underwater, along the seabed or ocean floor.
- Shield volcanoes are usually found at constructive or tensional boundaries.
- They are low, with gently sloping sides.
- They are formed by eruptions of thin, runny lava.
- Eruptions tend to be frequent but relatively gentle.