Coral limestone are examples of rocks whose formation is not explained by the rock cycle. Corals are tiny marine organisms that absorb carbon dioxide dissolved in sea water and use this to secrete hard skeletons of calcium carbonate. These organisms can build massive reef structures over the course of thousands of years.
The answer is the mid ocean ridge
Geography uses other subject in it's studies. Very close to geography are geophysics and geology. Geophysics studies quantitatively physical phenomena of the planet Earth, geology studies composition of soil rocks and their development through history. Geography uses biology, statistics, mathematics and other subjects in order to better describe the Earth.