Rock (geology)
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In geology, a rock is any naturally occurring solid mass or aggregate of minerals or mineraloid matter. It is categorized by the minerals included, its chemical composition, and the way in which it is
The Grand Canyon, an incision through layers of sedimentary rocks.
A balancing rock called Kummakivi (literally "strange stone")
Rock outcrop along a mountain creek near Orosí, Costa Rica.
Sample of igneous gabbro
Sedimentary rock
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Sedimentary rocks are types of rock formed by the cementation of sediments—i.e. particles made of minerals or organic matter —that have been accumulated or deposited at Earth's surface. Sedimentation
Rock (geology)
…it may include planetary geology that studies the rocks of other celestial objects. Rocks are usually grouped into three main groups: igneous rocks, sedimentary rocks and metamorphic rocks. Igneous rocks are formed when magma cools in the Earth's crust, or lava cools on the ground surface or the seabed. Sedimentary…
Middle Triassic marginal marine sequence of siltstones (reddish layers at the cliff base) and limestones (brown rocks above), Virgin Formation, southwestern Utah, U.S.
Uluru (Ayers Rock) is a large sandstone formation in Northern Territory, Australia.
Claystone deposited in Glacial Lake Missoula, Montana, United States. Note the very fine and flat bedding, common for deposits coming from lake beds further away from the source of sediment.
Sedimentary rock with sandstone in Malta, southern Europe