OCR B Geography GCSE Global Hazards

ash cloud

a cloud formed of small particles of fractured rock injected into the atmosphere. Can travel long distances depending on the size of the eruption.

sulphur deposit

often found near fumeroles which can be used in industry and provides jobs in some parts of the world.

geothermal power

power generated by capturing the heat of the earth, usually by harnessing steam and using it to drive turbines.

Pyroclastic flow

an avalanche of ash and hot, toxic expanding gas, traveling very fast down the flank of a volcano

Lava flow

a sheet of molten rock that flows over the ground surface and then solidifies.

glacier

a frozen river of ice formed by snow and ice accumulating in mountains or polar areas, which can even form on top of volcanoes (e.g. in Iceland)

sub-glacial

refers to processes or landforms underneath a glacier.

mitigation

the action of trying to reduce the impact of a hazard, by planning, predicting and preparation (e.g. building earthquake-resistant buildings)