1)When two plates move apart, lava will rise up through the gap created 2)As the magma rises, it solidifies and new land will be formed. 3)Layers and layers of this lava will form and a volcano will form.
2)Destructive
1)At destructive margins, an oceanic crust is submerged into magma under a continental plate. This is because oceanic plate is larger. 2)The part of the oceanic plate which is submerged then melts into magma. 3) This creates additional pressure in the mantle. 4)This pressure is released violently through cracks in the surface. 5) Mounds of lava will flow out of the crack. Slowly forming the base of the volcano. 6) After a while, the volcano will start to grow in size as the lava slowly piles on top of itself.