SCIENCE Q4

• Composed of the different continents

  Continental Crust
• the outermost layer found under the ocean

  Oceanic Crust
• irregularly shaped slab of solid rocks

  Tectonic Plates
• the idea of plates moving is called

  Continental Drift
• the layer of rocks in the crust is called

  Lithosphere
• pangea splits into two and created

  Laurasia and Gondwanaland
• occurs where tectonic plates collide

  convergent PB

  
• occurs when two plates moves apart from each other

  Divergent PB

  
• occurs when two plates slide past each other

  Transform PB

  
• the area above the focus

  epicenter
• the weakest part where the slippage of rocks occurs

  focus
• Intensity


  Measure of how much damage earthquakes cause on the surface
• Focus


  The weakest part where the slippage of rocks occur
• Magnitude


  The energy released by an earthquake
• Seismograph


  Measures the magnitude of an earthquake
• Epicenter


  The area above the focus
• Volcano


  Opening of earth's crust where lava and volcanic materials are ejected
• Crater


  A steep-walled depression at the peak of the volcano
• Volcanic vent


  A cylindrical channel that connects the crater to the magma chamber
• Caldera


  Formed when the summit of the volcano collapses
• Lava


  Molten rock that flows on the surface of the volcano
• Magma


  Hot liquid below the surface of the Earth
• Shield Volcano


  • Wide base with gentle sloping sides, cone made up of lava that has poured out and solidified during mild or quiet eruption
• Cinder Volcano


  • Narrow base and very steep slope, built almost entirely of loose fragments called cinders (pyroclasts and tephra)
• Composite Volcano or Stratovolcano


  • Composed of alternating layers of lava and cinders, formed when volcanic eruptions vary between quiet and violent or explosive
• Active Volcano


  Currently erupting or showing regular signs of activity like earthquake and significant gas emissions
• Dormant Volcano


  Have currently erupted and then have entered a long period of inactivity
• Extinct Volcano


  Have not shown signs of inactivity for a long period of time
• Explosive or Violent Eruption


  • The lava ejected is torn into shreds, forming pieces of pyroclastic materials called tephra, very violent explosive eruptions are called Plinian eruptions
• Quiet or Non-explosive Eruption


  • Basaltic magma has relatively low silica readily from it, the volcanic eruption is mild and a gentle flow of lava follows
• The release of magma from the crater is called an earthquake.
• Pyroclastic materials consist of lava, ashes and rocks.
• Volcanic eruption may only last for few minutes.
• When magma flows on the surface, it is already called a lava.
• When lava just flows out of the crater and gaps along sides of the volcano, it is an explosive eruption.
• Agricultural Benefits


  Soil becomes fertile
• Energy Benefits


  With a ready supply of water and a steady source of heat, steam can be generated to power turbines that can spin generators to produce electricity
• Industrial Benefits


  Volcanoes contain a very rich amount of minerals such as gold, silver, and copper
• Economic and Recreational Benefits


  Volcanoes promote tourism
• Effects of volcanic gases


  Volcanic ash like sulfur dioxide, nitrous oxide, and hydrochloric fumes can lead to acid precipitation