Describe and explain the distribution of volcanoes (10 marks)
- Make sure you have a clear structure – write an introduction, then describe where they occur, followed by a section explaining why volcanoes occur there
- In the introduction, define ‘Volcano’, e.g. ‘A volcano is a point where magma has risen from below the Earth’s surface and been ejected above ground’.
- Next describe the global distribution of volcanoes, e.g. ‘Volcanoes can be found all along the mid-Atlantic Ridge. They are also found around the edges of the Pacific Ocean (Ring of fire), particularly around Japan and Indonesia, and along the west coast of America. They are also found in the centre of the Pacific Ocean in Hawaii’.
- Now explain why volcanoes happen at each of the locations you have described. Make sure you use appropriate language, e.g. ‘The mid-Atlantic Ridge is a constructive boundary. Here the mantle is under pressure from the overlying plates, and when they move apart pressure is released and the mantle melts, forming magma. This is less dense than the plates so it rises and can erupt to form a volcano.