The structure of the earth
crust: made from rock
Mantle: made from molten and semi molten rock
outer core: molten and made from Nickle and iron
inner core : solid ball made from Nickle and iron
moving plates
oceanic plate: occurring under ocean
continental plate under continents
plate boundaries: where two plated meet and are separated by faults
convection currents
stage 1: heat from the earth’s core causes magma to heat up and rise
stage 2: when hot magma reaches under the earth’s crust it moves in all directions dragging the crust with it
stage3: the hot magma cools as it is further from the core this makes it heavier
stage4: when magma cools it sinks towards the core where it is reheated
stage 5:this cycle is repeated again and again causing convection current
constructive plate boundaries
happens where 2 plates are moving away from each other
the plates are pulled apart by convection currents , molten magma comes to the surface through a crack called a fissure and creates new land
earthquakes ,new land, volcanos, mid ocean ridge
destructive plate boundaries
convection currents causes two plates to collide
heavier plate sinks below the lighter plate and is destroyed
the lighter plate rises forming fold mountains
feature: fold mountains volcanos earthquakes
constructive plate boundaries
two plates move side by side
they can move in the opposite directions or the same direction but a diffrent speeds
sometimes the plates get stuck eventually the plates slip forward suddenly the energy released causes earthquakes