| A | B |
|---|
| Rock | A solid material in the earth's crust that is a natural combination of minerals or other materials. |
| texture | How a rock looks and feels based on the sizes of the mineral grains and other particles that compose the rock. |
| grain | Pieces and particles of mineral crystals, rock fragments, and even fossils in a rock that determine its texture. |
| igneous | A rock formed from solidified magma or lava. |
| pegmatite | A coarse-grained igneous rock with very large interlocking crystals. |
| porphyry | An igneous rock containing a few large mineral grains embedded in a very fine textured matrix. |
| phanerite | An igneous rock composed of distinct mineral grains that are small and more or less the same size. |
| aphanitic | Fine-grained igneous rock with crystals too small to see, even with a microscope; often extrusive igneous. |
| sedimentary rock | A rock made of sediments produced by erosion or chemical preciptiation. |
| clast | A piece of broken or eroded rock. Range in size from microscopic to boulder-sized fragments. |
| clastic sedimentary rock | A rock made from the eroded fragments of other rocks. |
| nonclastic sedimentary rock | A sedimentary rock composed of materials that are not clastic erosion sediments. |
| chemical sedimentary rock | A rock composed of chemical precipitates |
| precipitation | In geology, any process that causes chemical substances dissolved in water to form a solid compound that settles out of solution. |
| metamorphic rock | An igneous, sedimentary , or even another metamorphic rock that seems to have been physically and chemically changed over time by temperature, pressure , or the presence of hydrothermal fluids. |
| regional metamorphism | Metamorphism that occurred over large areas caused by widespread, regional tectonic forces, heat, or the pressure from the weight of overlying rock. |
| contact metamorphism | Metamorphism caused mainly by contact with high-temperature magma or lava. |
| dynamic metamorphism | Metamorphism that occurred when conditions rapidly changed in rocks; can occur in rocks near very active faults. |
| foliated metamorphic rock | Metamorphic rock containing flattened or flaky mineral crystals, giving it a banded or layered appearance. |
| nonfoliated metamorphic rock | A metamorphic rock that doesn't have bands or layers and tends to break into sharp angular pieces. |
| rock cycle | A naturalistic, old-earth idea that rock is recyled just like nearly every other natural resource. |
