New rocks are constantly being created through the rock cycle.
The rock cycle represents the sequence through which new rocks are formed and old rocks are recycled. Many different geological processes contribute to the rock cycle. Some occur only deep below the Earth, but several are in progress every day all around us on the surface.
Igneous Rock Formation
All rocks start out as magma or molten rock. While most igneous rock forms underground, volcanoes and areas along tectonic plate boundaries regularly deposit new rock onto the surface. New islands are created constantly and in some cases, very large islands are formed like the Hawaiian Islands or the country of Iceland.
Weathering
Once any rock formation is exposed to the elements on the surface, it will slowly be broken down by weather. Rain slowly dissolves and breaks apart rock, and during temperature changes water will turn into ice within small cracks and mechanically break down boulders. Release of stress at the surface also fractures rock bodies as they expand in their new environment, most notably at Half Dome in Yosemite National Park.
Sediment Transport
As material weathers it becomes smaller in size. Eventually it can be carried away by wind and water. Although catastrophic events can move huge boulders, most sediment is suspended as tiny grains in rivers and streams. In particularly dry areas the wind moves sand and small particles, which can form giant dunes.
Deposition
Transported material is eventually deposited. Deltas are common depositional landforms at the mouth of rivers, but any place from deserts to the bottom of the ocean can be an area of deposition. Deposition occurs in low energy environments when the amount of suspended load exceeds the carrying capacity of the water or air. Over time, enormous amounts of sediment will start to compact and undergo diagenesis and continue in the rock cycle.
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