Tectonic hazards

• Tectonic hazards


  Hazards caused by movements of the Earth's tectonic plates, such as earthquakes and volcanic eruptions
• Tectonic hazards can vary depending on a country's wealth
• You need to know about tectonic hazards in contrasting countries - they could be earthquakes or volcanic
• New Zealand


  Country that suffered a 7.8 magnitude earthquake in 2016
• New Zealand earthquake occurred

  14th November 2016
• GDP per capita


  US $40,131
• Tectonic setting of New Zealand


  • Plate boundary: Dextral (right-lateral) transform fault - the Pacific plate is sliding past the Australian plate to the north and south
• The earthquake measured 7.8 on the moment magnitude scale
• The New Zealand earthquake was the same magnitude as an earthquake in Nepal in 2015
• Nepal


  Country that suffered a 7.8 magnitude earthquake in 2015
• Nepal earthquake occurred


  25th April 2015
• GDP per capita


  US $60
• Tectonic setting of Nepal


  • Plate boundary: Convergent - the Indo-Australian plate is being subducted beneath the Eurasian plate
• The Nepal earthquake measured 7.8 on the moment magnitude scale
• Nepal's response was slower and less effective than New Zealand's
• Many people live in areas affected by tectonic hazards, even though they are aware of the risks
• Some people choose to live in hazardous regions, for example around 1 million people live on the slopes of Mount Etna in Italy
• Reasons people choose to live in hazardous regions


  • They've always lived there and don't want to leave their jobs or families
  • They're confident their government will support them after a disaster
  • The volcanic soil is very fertile, attracting farmers
  • Volcanoes are tourist attractions, so people live nearby to work in the tourism industry
• Monitoring tectonic hazards


  • Earthquakes - seismometers and lasers monitor earth movements to provide early warning
  • Volcanoes - scientists monitor for signs of an impending eruption, such as earthquakes, gas release, and changes in the volcano's shape
• Predicting tectonic hazards


  • Earthquakes - cannot be reliably predicted, but scientists can identify where they may occur by monitoring plate movements
  • Volcanic eruptions - can be predicted if volcanoes are monitored closely
• Protecting against tectonic hazards


  • Earthquakes - new buildings can use reinforced concrete, and existing buildings can be strengthened with steel frames. Automatic shut-off switches can turn off gas and electricity supplies.
  • Volcanoes - buildings can be strengthened to withstand ash fall, and barriers have been used to try to divert lava flows, with limited success.
• Planning for tectonic hazards


  • Future developments can avoid high-risk areas
  • Emergency services can plan rescue operations
  • People can be educated on what to do in the event of a hazard
  • Evacuation routes can be planned to get people away quickly
  • Emergency supplies can be stockpiled
• Global atmospheric circulation patterns influence the effects of tectonic hazards
• Global atmospheric circulation


  Air circulates globally due to differences in temperature and pressure, creating wind patterns like the Coriolis effect
• Global atmospheric circulation patterns can affect the distribution of ash and gases from volcanic eruptions