L4 - Understanding tectonic hazards

• natural hazard

  an occurence over which people have little or no control, which poses a threat to peoples lives and possessions. it is different from a natural event, as volcanoes can erupt in an unpopulated area without causing any damage
• primary effect

  the immediate effects of the eruption, caused by it directly
• secondary effect

  the after effects that occur as an indirect effect of the eruption on a longer timescale
• impacts

  what happens to life and/or property as a result of a natural hazard
• short term response

  how people react as the disaster happens and in the immediate aftermath of the event
• long term response

  later reactions that occur in the weeks, months and years after the event
• monitoring

  looking for signs of an eruption using observation, tilt meters, GPS, digital cameras on the crater, emission of sulphur dioxide and using robots called ‘spiders’ to look for changes
• prediction

  using monitoring of the volcano, past frequency of eruptions, patterns of lava flows, ash movements and lamar’s to determine how the volcano is likely to behave to enable effective evaluation
• GPS

  global positioning systems use satellites orbiting the earth to detect movements of the land and heat changes
• dormant

  a volcano that is not currently erupting but is likely to erupt in the future
• active

  a volcano that is erupting or has erupted in recorded history
• extinct

  a volcano that shows no signs of ever erupting again
• tiltmeter

  a type of technology that detects a change in slope on a volcano caused by shifting magma beneath the surface, predicting an eruption
• ring of fire

  an area where large numbers of earthquakes and volcanic eruptions occur in the basin of the pacific ocean. in a 40,000 km horseshoe shape, it is associated with nearly a continuous series of oceanic trenches, volcanic arc, and volcanic belts and/or belt movements. it has 452 volcanoes and is home to over 75% of the worlds active and dormant volcanoes
• aid

  money, food, training and technology given by richer countries to poorer ones, either to help with an emergency or to encourage long term development
• pyroclastic flow

  a flow of volcanic ash, dust, rocks and debris that cascades down the slope of a volcano during an eruption. very dangerous, reaching speeds greater than 60 mph and temperatures in excess of 800 degrees
• lahar

  a secondary effect of a volcanic eruption which are mudflows created by volcanic ash mixing with melted ice or water
• lava bomb

  a block of lava ejected into the air from a volcano. as it is thrown out, it cools and spins, causing the block to be rounded
• tephra

  a general term for fragments of rock, ash and lava that are blasted into the air by explosions or carried by hot gases in eruption columns
• tsunami

  a very large and destructive wave, generally caused by a disturbance in the ocean, such as an undersea earthquake or volcanic eruption
• effects of tectonic hazards

  deaths, injuries and people made homeless
• effects of tectonic hazards

  several aftershocks led to people being afraid to go home
• effects of tectonic hazards

  the tsunami swept away everything in its path
• effects of tectonic hazards

  people were digging with their bare hands to get to survivors
• effects of tectonic hazards

  avalanches and landslides swept away homes
• effects of tectonic hazards

  schools and hospitals were destroyed
• effects of tectonic hazards

  floods and mudflows wiped out roads
• effects of tectonic hazards

  cholera and typhoid caused many more deaths in the refugee camps
• effects of tectonic hazards

  tourism is a big part of the job market but due to this disaster, tourism declined quickly in this area
• effects of tectonic hazards

  the university shut down due to a lack of students wanting to study here
• effects of tectonic hazards

  rice fields were destroyed leading to food shortages and starvation
• effects of tectonic hazards

  fires raged and destroyed vast areas of forest
• effects of tectonic hazards

  in the subsequent years, farmers yields were higher due to the fertile soils
• effects of tectonic hazards

  locals became tour guides to show around the tourists that came
• effects of tectonic hazards

  food, water and electricity supplies were reduced
• effects of tectonic hazards

  people couldn’t contact family due to power cables being down
• effects of tectonic hazards

  historic buildings and temples were destroyed
• effects of tectonic hazards

  many animals were asphyxiated
• effects of tectonic hazards

  damage estimated in the millions of $
• an earthquake is a sudden and brief period of intense ground shaking