"The rock cycle is like a well oiled clock. Take out one gear and the rest falls with it. The rock cycle is very dependant on Ingneous rocks or there would be no rocks. They also depend on Metamorphic, take out metamorphic and you run out of lava to make rocks from. If you take out sedimentary rocks there would be no rocks to turn into metamorphc, and when theres no metamorphic, no more rocks."