RocksWord Definition Knowledge connection

(examples or facts)Sedimentary rocks

Formed when particles from other rocks or the remains of plants and animals are pressed and cemented together

Igneous rocks Formed from the cooling of molten rock at or below the surface

Metamorphic rocks

Formed from an existing rock that is changed by heat, pressure, or chemical reactions

Extrusive rock Formed from lava on the earth’s surface

Intrusive rock Igneous rock that forms when magma hardens beneath Earth’s surface

Porphyritic Igneous rocks with large crystals scattered on a background of much smaller crystals, cooled in two stages

Foliated Metamorphic rock whose grains are arranged in parallel layers or bands

Deposition Process by which sediment settles out of the water or wind that is carrying it, and is deposited in a new location

Clastic rock Sedimentary rock formed when rock fragments are squeezed together under high pressure

Organic rock Sedimentary rock that forms where remains of organisms are deposited in thick layers

Chemical rock Sedimentary rock formed when minerals crystallize from a solution

Coral reef Structure of skeletons built up by coral animals in warm, shallow ocean water

atoll Ring-shaped coral island found far from land