Notes

convection current:
the core heats up the magma, causing it to expand and rise. As the heated magma spreads and moves away from each other, the plates are dragged away from each other. The magma loses heat and sinks, the plate are dragged towards each other. The core heats up the magma again ans the cycle repeats.
Slab-pull force:
The denser oceanic plates subducts under the less dense continental plate. The subducted place drives the downward portion of the convection current while the material away from the subducting plate drives the upward portion of the convection current.
O-O divergence:
When two oceanic plates diverge, magma rises from the mantle to fill in the gap between the plates as they move apart. New sea floor is formed as the magma cools and solidifies, the process is called sea floor spreading. A mid-oceanic ridge is formed, the younger crust is found nearer the spreading zone while the older crust is found further away from it.
C-C divergence:
when two continental plates diverge, they are stretched due to tensional forces, forming fractures at the plate boundary. this is called faulting. The land in between the two continental crusts sinks forming a linear depression known as a rift valley. The two blocks of land standing is called block mountains.
O-O convergence:
when two oceanic plates converge, the denser oceanic plate subducts under the less dnese oceanic plate. Oceanic trenches are formed at the subduction zone. The subducted plate causes the mantle material above it to melt and form magma. Magma rises through the crust forming volcanoes
C-C convergence:
When two continental plates converge, the crusts collide and are compressed together. The plates are not subducted as they are too buoyant. Due to compressional forces, the layer of rocks buckle and fold upwards and form fold mountains
O-C convergence:
when an oceanic plate converges with a continental plate, the denser oceanic plate subducts under the less dense continental plate. Oceanic trenches are formed at the subduction zone. The subduted plate causes the mantle material above it to melt to form magma. Magma rises and forms volcanoes on lend. The edge of the continental plate buckle and fold upwards forming fold mountains.