| A | B |
|---|
| texture | the size, shape, and pattern of a rock's grains |
| grain | a particle of mineral or other rock that gives a rock its texture |
| igneous rock | a type of rock that forms from the cooling of molten rock at or below the surface |
| sedimentary rock | a type of rock that forms when particles from other rocks or the remains of plants and animals are pressed and cemented together |
| metamorphic rock | a type of rock that forms from an existing rock that is changed by heat, pressure, or chemical reactions |
| extrusive rock | igneous rock that forms from lava on Earth's surface |
| basalt | a dark, dense igneous rock with a fine texture, found in oceanic crust |
| intrusive rock | igneous rock that forms when magma hardens beneath Earth's surface |
| granite | a usually light-colored rock that is found in continental crust |
| porphyritic texture | an igneous rock texture in which large crystals are scattered on a background of much smaller crystals |
| silica | a material that is formed from the elements oxygen and silicon; silica is found in magma |
| sediment | small, solid particles of material from rocks or organisms which are moved by water or wind, resulting in erosion and deposition |
| erosion | the process by which water, ice, wind or gravity moves fragments of rock and soil |
| deposition | the process by which sediment settles out of the water or wind that is carrying it, and is deposited in a new location |
| compaction | the process by which sediments are pressed together under their own weight |
| cementation | the process by which dissolved minerals crystallize and glue particles of sediment together into one mass |
| clastic rock | sedimentary rock that forms 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 that forms when minerals crystallize from a solution |
| coral reef | a structure of calcite skeletons built up by coral animals in warm, shallow ocean water |
| atoll | a ring-shaped coral island found far from land |
| foliated | term used to describe metamorphic rocks whose grains are arranged in parallel layers or bands |
| rock cycle | a series of processes on the surface and inside Earth that slowly changes rock from one kind to another |
