Tectonic hazards

• Afghanistan, 21 June 2022: BBC news report written 5 days after the earthquake
• In Afghanistan's south-eastern Paktika province, the majority of homes have been completely destroyed by the earthquake
• The structures still standing have deep cracks running through them, making them too dangerous to live in
• The village of Dwegur, located high on the mountainside, is home to 250 people. As a result of its remote location, no-one from the Taliban government or aid agencies have reached it with help so far
• Before us, no journalists had been there either
• At the northern edge of the village, 20-year-old Arafat's house used to stand on a slope. Now it's a pile of rubble-stones, window frames and personal belongings lie amid the ruins
• "That night I heard a sound like a big explosion and something hit my head hard. I thought I was going to die. But I managed to crawl out from under the rubble," he said
• "There is so much hunger and sadness in my village. No-one has come to help us."
• They have strung plastic sheets and pieces of cloth between bamboo sticks stuck into the ground. Women sleep in the makeshift tents. The men sleep outside
• In these mountainous areas, thunderstorms are a frequent occurrence
• Aid has arrived about an hour away in Gayan: food and other relief material from charities, and some from the Taliban government
• Even getting to that point from the nearest town requires travelling for hours on mud tracks that wind around mountains and cross rivers
• Afghanistan needs a lot of support, not just in the form of food packages and relief material but also help to reach these remote areas
• Perhaps an air force or trained disaster response teams could achieve that but the Taliban do not have such resources
• Even before the earthquake people in the village barely had enough to get by. Some work as labourers, others forage pine nuts from the forest on the mountains around the village
• These communities have no savings to help them rebuild
• For now, the people have been left on their own to deal with the aftermath of an earthquake, scared that a new one might strike at any time
• Tectonic plates


  Sections of the earth's crust that float on the mantle and are moved around by convection currents
• Continental plates


  • Thick, relatively light and very old
• Oceanic plates


  • Thinner, denser and younger
• Convection currents


  Circular flows of magma which move tectonic plates
• Slab pull


  The process of older, denser sections of crust subducting (sinking) into the mantle and pulling sections of new lighter crust with it
• Ridge push


  Lava erupts to create crust as plates move apart. As it cools, it pushes down the slope of the ridge, pushing the plates even further apart
• Destructive plate margin


  1. Two plates move towards each other

  2. Oceanic plate subducts into the mantle

  3. Magma rises to create volcanoes

  4. Pressure causes continental plate to fold upwards into mountains
• Destructive plate margin


  • Between the South American and Nazca Plate
• Collision destructive plate margin

  1. Two continental plates move together

  2. Neither plate subducts

  3. Both plates fold upwards to create fold mountains
• Collision destructive plate margin


  • Where the Indo-Australian and Eurasian plates collide, creating the Himalayas
• Conservative plate margin


  1. Plates move alongside each other

  2. Pressure builds up and is suddenly released in earthquakes
• Conservative plate margin


  • Boundary between the North American and Pacific plates
• Constructive plate margin


  1. Plates move apart

  2. Magma rises up and erupts to form a mid-oceanic ridge
• The Christchurch earthquake in New Zealand in 2013 occurred at a conservative plate margin between the Pacific Plate and the Australasian Plate
• As the plates became locked together, pressure built up until it was suddenly released, causing a 6.3 magnitude earthquake
• The earthquake caused significant damage, killing 185 people and destroying many buildings
• Liquefaction caused further damage to infrastructure like roads and water pipes
• The damage was estimated to cost over $28 billion and have a long-term impact on the economy
• New Zealand's disaster response helped the injured and homeless, and reconstruction efforts continued for many years
• The Canterbury Earthquake Recovery Authority was created to organise the rebuilding and improve planning laws to protect the city from future earthquakes