A summary of the rock cycle?

Answer 1

The rock cycle started with the molten rock that made up the early surface of planet Earth.

When the Earth cooled the molten lava solidified into igneous rock. Igneous rock that cooled quickly (such as on the surface) formed smaller crystals whereas those that cooled slower (such as under the surface) have larger crystals.

Over time the effects of chemicals, heat and pressure (such as from underground magma flow) can transform the structure of igneous rock. This change forms metamorphic rock.

Metamorphic and igneous rock can be worn down by the effects of erosion. Acid rain, rain, wind, expansion and contraction of ice, earthquakes and other factors will wear down rocks to smaller pieces. These smaller pieces can be transported by landslides and water flows (at which time they can be eroded further).

Eventually very small particles of rock are carried by rivers out to sea where they are deposited on the ocean floor. Over millions of years layers of rock particles are laid down in layers. These layers are crushed over time and squeezed both by the tonnes of water above and the rock layers. Eventually these particles are squashed together to form sedimentary rock.

form igneous rock.

As can be seen the rock cycle can now cycle from any rock type to any other rock type. The rock cycle will always be going on and on.

Answer 2

Basically, old rocks are being broken down or changed and new rocks are being created.