Science: Layers of the Earth and Earthquakes

• Crust - this layer is made up of several large and small plates.
• Mantle - it is the widest layer of the Earth and is made up of magma.
• Core - the central layer of earth and is divided into a liquid layer called outer core and a solid later called inner core.
• What is the liquid layer of the Earth?

  Outer core
• What is a solid layer of the Earth?

  Inner core
• An earthquake is the shaking of the ground.
• Volcanic - happens with a strong volcanic eruption.
• Tectonic earthquakes - is caused by the movement of the Earth's crust.
• A tectonic earthquake may occur above the ground or beneath the ocean.
• Focus - is the break in the ground caused by the pressure of the moving rocks.
• Magnitude - refers to the amount of energy released by an earthquake from its focus.
• Epicenter - The ground above the focus, that an earthquake is felt the strongest.
• Ritcher scale - is used to measuring an earthquake's magnitude.
• Tectonic plates - the Earth's crust is broken into smaller pieces.
• What are the three types of tectonic boundaries:

  • Convergent
  • Divergent
  • Transform plate
• Divergent boundary - happens when two plates move away from each other.
• Divergent boundary - happens when two plates move away from each other.
• Convergent boundary - occurs when two plates move towards each other.
• Transform plate boundary - occurs when two plates sliding past each other.
• Convection currents - the movement refers when heat and pressure in the asthenosphere cause the movement of molten rocks.
• Magma - it is produced when the high temperature and pressure results in melting rocks.
• The magma that flows out on the surface is called lava.
• An eruption is explosive when large amounts of pyroclastiv materials are ejected by the volcano into the air.
• In a non-explosive eruption, lava just flows out of the crater and gaps along the sides of the volcano.
• Pyroclastic materials consist of lava, ashes, volcanic glass and rocks.
• Intensity - an effect by an earthquake's magnitude.
• Seismic waves are waves that travel through the Earth's layers and give out low-frequency.
• Volcanic earthquakes occur when movement of the plates an the Earth's crust is caused by volcanic activity.
• Earthquakes change the Earth's surface by causing the land to move up, down or sideways.
• Landslides due to earthquake make changes to the Earth's surface as well.
• Active volcanoes - are easy to recognize because they often erupt.
• Dormant volcanoes - are presently inactive but may erupt again.
• Extinct Volcanoes - are considered unlikely to erupt in the future.
• Lavabeds - creating by the magma quietly oozes up through great cracks in the crust under the ocean and spreads out the surface of the ocean.
• Lahar or the mudflow of the volcanic materials can destroy forests and bury fields.
• A volcanic eruption is one of the most destructive natural forces on earth.