Restless Earth 1.1

The Restless Earth entire specification.

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  • Restless Earth 1.1
    • The Earth's crust is unstable, especially at plate margins
      • Distribution of plates (refer to poster)
      • The centre of the earth is the core (inner and outer), the mantle is around that (semi molten rock, moves in convection currents) followed by the crust.
        • The crust is divided into continental (thicker and less dense, newer, can't sink or be renewed or destroyed) and oceanic (thinner and more dense, older, can sink and can be renewed and destroyed).
      • Destructive plate margins are ones where two plates are moving towards eachother.
    • Volcanoes are hazards resulting from tectonic activity. Their primary and secondary effects are positive as well as negative. Responses change in the aftermath of an eruption.
      • Scientists try to monitor the tell-tale signs that come before a volcanic eruption. Things such as tiny earthquakes, escaping gas, and changes in the shape of a volcano (eg, bulges in the land where magma has built up under it) all mean an eruption is likely.
    • Supervolcanoes are on a much bigger scale than other volcanoes and an eruption would have global consequences.
      • Supervolcanoes develop on hotspots (Yellowstone Park) and at destructive plate margins
      • 1. Magma rises up through cracks in the crust creating a large magma basin below the surface. The pressure of the magma causes a circular bulge on the surface several km wide.
        • 2. The bulge eventually cracks, creating vents for lava to escape through.The lava erupts out of the vents causing earthquakes and sending up gigantic plumes of ash and rock
          • 3. As the magma basin empties, the bulge is no longer supported so it collapses, spewing up more lava.
            • 4. After the eruption, there's a caldera (big crater) left where the bulge collapsed. Sometimes these are filled with water to form a large lake (Lake Toba)
      • A supervolcanic eruption will erupt thousands of km cubed of rock, ash and lava. A thick cloud of super-heated gas and ash will flow at high speed from the volcano, killing, burning and burying everything it touches. Everything within tens of miles will be destroyed.
      • Ash will shoot kms into the air and block out almost all daylight over whole continents. This can trigger mini ice ages as less heat energy from the sun gets to Earth
    • Earthquakes occur at constructive, destructive and conservative plate margins; the effects are responses of them differ due to contrasts in levels of wealth.
      • Earthquakes occur at all three types of plate margin.
        • At destructive margins, tension builds up when one plate gets stuck as it's moving down past the other into the mantle.
        • At constuctive margins, tension builds along cracks within the plates as they move away from eachother.
        • At conservative margins, tension builds up when plates that are grinding past eachother get stuck
      • The plates eventually jerk past eachother, sending out shock waves (vibrations). These spread out from the focus (starting point). Near the focus the waves are stronger and cause more damage. The epicentre is the point on the earth's surface straight above the focus. Weak earthquakes are common; strong ones are rare.
      • The Richter scale measures the amount of energy released by the earthquake (the magnitude) using a seisometer. It doesn't have an upper limit and it's logarithmic.
        • The Mercalli scale measures the effects of an earthquake by asking eye witnesses of observations of what happened. It's a scale of 1-12.
          • Earthquakes occur at constructive, destructive and conservative plate margins; the effects are responses of them differ due to contrasts in levels of wealth.
            • Earthquakes occur at all three types of plate margin.
              • At destructive margins, tension builds up when one plate gets stuck as it's moving down past the other into the mantle.
              • At constuctive margins, tension builds along cracks within the plates as they move away from eachother.
              • At conservative margins, tension builds up when plates that are grinding past eachother get stuck
            • The plates eventually jerk past eachother, sending out shock waves (vibrations). These spread out from the focus (starting point). Near the focus the waves are stronger and cause more damage. The epicentre is the point on the earth's surface straight above the focus. Weak earthquakes are common; strong ones are rare.
            • The Richter scale measures the amount of energy released by the earthquake (the magnitude) using a seisometer. It doesn't have an upper limit and it's logarithmic.
              • The Mercalli scale measures the effects of an earthquake by asking eye witnesses of observations of what happened. It's a scale of 1-12.
      • Tsunamis are a specific secondary effect and can have devastating effects in coastal areas.
        • If earthquakes happen at sea they can cause tsunamis.
          • The entire sea or ocean is set in motion by an event, often an earthquake, which displaces the water above it and causes a huge wave.
    • Constructive margins are where two plates are moving away from eachother. Magma rises from the mantle to fill the gap and (cools, creating new crust)/(creates a volcano).
      • The Earth's crust is unstable, especially at plate margins
        • Distribution of plates (refer to poster)
        • The centre of the earth is the core (inner and outer), the mantle is around that (semi molten rock, moves in convection currents) followed by the crust.
          • The crust is divided into continental (thicker and less dense, newer, can't sink or be renewed or destroyed) and oceanic (thinner and more dense, older, can sink and can be renewed and destroyed).
        • Destructive plate margins are ones where two plates are moving towards eachother.
    • Shield volcanoes are made up of only lava. The lava is runny and flows quickly, spreading over a wide area; forming a low, flat volcano.
      • At destructive  margins ocean trenches and volcanoes can be formed. Constructive margins can also create volcanoes and some form over 'hotspots' - parts of the mantle that are particularly hot.
        • Unique landforms occur at plate margins
          • Restless Earth 1.1
            • Volcanoes are hazards resulting from tectonic activity. Their primary and secondary effects are positive as well as negative. Responses change in the aftermath of an eruption.
              • Scientists try to monitor the tell-tale signs that come before a volcanic eruption. Things such as tiny earthquakes, escaping gas, and changes in the shape of a volcano (eg, bulges in the land where magma has built up under it) all mean an eruption is likely.
            • Supervolcanoes are on a much bigger scale than other volcanoes and an eruption would have global consequences.
              • Supervolcanoes develop on hotspots (Yellowstone Park) and at destructive plate margins
              • 1. Magma rises up through cracks in the crust creating a large magma basin below the surface. The pressure of the magma causes a circular bulge on the surface several km wide.
                • 2. The bulge eventually cracks, creating vents for lava to escape through.The lava erupts out of the vents causing earthquakes and sending up gigantic plumes of ash and rock
                  • 3. As the magma basin empties, the bulge is no longer supported so it collapses, spewing up more lava.
                    • 4. After the eruption, there's a caldera (big crater) left where the bulge collapsed. Sometimes these are filled with water to form a large lake (Lake Toba)
              • A supervolcanic eruption will erupt thousands of km cubed of rock, ash and lava. A thick cloud of super-heated gas and ash will flow at high speed from the volcano, killing, burning and burying everything it touches. Everything within tens of miles will be destroyed.
              • Ash will shoot kms into the air and block out almost all daylight over whole continents. This can trigger mini ice ages as less heat energy from the sun gets to Earth
            • Tsunamis are a specific secondary effect and can have devastating effects in coastal areas.
              • If earthquakes happen at sea they can cause tsunamis.
                • The entire sea or ocean is set in motion by an event, often an earthquake, which displaces the water above it and causes a huge wave.
    • The ash will also settle over hundreds of km squared, burying fields and buildings (ash from normal volcanoes usually covers a couple of km squared).

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