Tectonics

• Constructive plate boundary.

  Two plate move apart due to convection currents. This creates a gap, hot lava from the mantle is able to reach the surface. This creates new crusts and causes small volcanos.
• Destructive plate boundary

  Oceanic plate goes under a continental plate causing pressure to build up as it is denser. The oceanic plate turns to magma due to the heat. The magma rises through the gaps in the continental plate, if it reaches the surface it causes a volcano.
• Example of constructive plate boundary

  Mid-Atlantic Ridge
• Example of destructive plate boundary

  Nevada del ruiz, Columbia
• Collision plate boundary

  Where two continental plates meet and buckle to form fold mountains
• Transform plate boundary (conservative)

  Two plates slide along a fault. No volcanos are found along this plate but earthquakes do occur.
• Example of a collision plate boundary

  Himalayas
• Examples of transform plate boundary

  San Andreas Fault
• Characteristics of a shield volcano

  - gentle slopes

  - wide bases

  - frequent eruptions of basic lava

  - non-violent (gap has been created)
• Characteristics of composite volcano

  - steep sided cone shape

  - high narrow base

  - lava is thick and viscas (high silica content)

  - lava doesn't flow easily
• Example of Sheild Volcano

  E10, iceland
• Example of composite volcano

  Mount Vesuvius
• Social impacts of E10

  People got isolated, upset from damage
• Economic impacts of E10

  Ruined crops, flood damage cost
• Environmental impacts of E10

  Fallen trees, mud, lots of rocks
• Why was there concern of flooding during E10

  Ice was melting due to the heat and large amounts of water had been produced
• How did E10 boost tourism

  - people wanted to see where the eruption took place

  - 1.7 million people visited in 2016

  - lava built a visitor centre

  - boosted tourism 5x
• The plus side of living near volcanos (soil)

  The physical and chemical weathering of volcanic rocks made the soil very fertile, meaning crops were easily grown here
• The plus side of volcanos (geothermal energy)

  Geothermal energy is all energy stored in the form of heat beneath the surface of the solid earth. It is a reliable and constant source of low-carbon, renewable heat that is not dependent on weather conditions. Geothermal heats over 70% of homes in Iceland.
• The plus side of volcanos (minerals)

  Lava in volcanos can crystallise to form minerals such as gold and diamonds depending on their mineral composition. Therefore volcanoes are excellent places for mining and creating job opportunities
• Plus side of volcanos (tourism)

  People around the world have a fascination with volcanos. Many tourists flock to places such as Iceland to catch a glimpse of a volcano. This creates many job opportunities for citizens.
• Plus side of volcanos (monitoring and predictions)

  Scientists study and monitor volcanos so that those living near active volcanos are more aware. Monitoring a volcano for a long period of time will indicate changes in the volcano before it erupts
• Richter scale

  The scale of which an earthquake is measured
• Magnitude

  How strong the earthquake is
• Focus

  The place in the earth where rocks are moving
• Epicentre

  The point at the surface above the focus
• After-shock

  Smaller earthquakes after the main, large one
• Siesometer

  An instrument to measure the strength of an earthquake
• How do earthquakes occur?

  Earthquakes occur at plate margins, as the plates move past each other at the margins the movement is not smooth. The plates sometimes lock causing pressure to build up, the pressure is released in a jerky movement. This release of pressure is called an earthquake
• Where is an earthquake strongest?

  epicenter
• If the focus is deeper in the earth

  The earthquake will be weaker as the seismic waves have further to travel
• Where is Christchurch

  South Island of New Zealand
• When was the Christchurch earthquake?

  Sept 2010, feb 2011
• Christchurch magnitude

  7.1 and 6.3
• Primary impacts of Christchurch

  185 deaths and 100,000 properties damaged
• Secondary impacts of Christchurch

  6 months with no clean water
• Rescue of Christchurch

  $6-7 million international aid, rescue crews from USA, UK
• How long for Christchurch to recover

  50-100 years and $28 billion
• Causes of christchurch

  Slippage along the alpine fault caused pressure to build up and a sudden jerk in the plate caused the earthquake
• Why was Christchurch aftershock more damaging?

  Shallow focus and nearer the city