term three sst

• earth is made up of crust, mantle and core
• crust

  crust is the thinnest layer we live upon as it is only 35km deep under UK. It is made up of granite and basalt with magnesium and sillica as common elements
• mantle

  the most thick layer 2900km deep under UK. it is solid and semisolid in some places, with soft, taffy-like consistency. it is always moving and causes tectonic activity
• core

  made up of iron and nickle
• core temp

  hottest part of earth, 6000 degrees Celsius
• inner core is solid, outer is liquid
• How did the layers form?

  earth was initially very hot, with melted rocks and minerals. dense rocks, like iron, sank to the centre (to form the core), and less dense rocks, like magnesium and silica, stayed at the surface to form the crust and mantle. Due to immense pressure, the outer core is liquid and the inner core is solid.
• what is oceanic crust

  this is the crust under the ocean. it is mainly made up of basalt and thinner than continental crust. oceanic crust is about 7 km deep.
• what is continental crust

  continental crust is the crust we live upon. it is made up of granite and is 30-50 km deep
• convectional current

  the process of heating and cooling a liquid. as volume increases--due to kinetic energy moving liquid particles further away—density decreases, so hot liquid floats up and cooler liquid stays at surface
• earthquake is the shaking of the earth's crust due to the movement of rocks and volcano is where lava erupts at the earth's surface. they often tend to lie around the lines, are often close together and occur on ocean and land
• explaining the pattern

  earth's hard outer layer is broken into slabs

  these slabs move around and slide/push other slabs

  these movements cause earthquakes/volcano eruptions
• tectonic plates

  earths crust in lithospheres divided in several slabs and are always on move due to convectional currents
• types of plates

  Divergent (plates move away and form gaps—volcano forms)

  Convergent (plates move towards each other other; trenches or folds of mountains form)

  Conservative (plates slide against each other—earthquakes)
• why do plates move?

  because plates are slabs of lithosphere and it's moved by convectional currents in soft rock