1.
basaltic: describes dense, dark-colored igneous rock formed from magma rich in magnesium and iron and poor in silica
2.
cementation: sedimentary rock-forming process in which sediment grains are held together by natural cements that are produced when water moves through rock and soil
3.
compaction: process that forms sedimentary rocks when layers of sediments are compressed by the weight of the layers above them
4.
extrusive: describes fine-grained igneous rock that forms when magma cools quickly at or near Earth's surface
5.
foliated: describes metamorphic rock, such as slate and gneiss, whose mineral grains line up in parallel layers
6.
granitic: describes generally light-colored, silica-rich igneous rock that is less dense than basaltic rock
7.
igneous rock: rock formed when magma or lava cools and hardens
8.
intrusive: describes a type of igneous rock that generally contains large crystals and forms when magma cools slowly beneath Earth's surface
9.
lava: molted rock that flows from volcanoes onto Earth's surface
10.
metamorphic rock: forms when heat, pressure, or fluids act on igneous, sedimentary, or other metamorphic rock to change its form or composition, or both
11.
nonfoliated: describes metamorphic rock, such as quartzite or marble, whose mineral grains grow and rearrange but generally do not form layers
12.
rock: mixture of one or more minerals, rock fragments, volcanic glass, organic matter, or other natural materials; can be igneous, metamorphic, or sedimentary
13.
rock cycle: model that describes how rocks slowly change from one form to another through time
14.
sediment: loose materials, such as rock fragments, mineral grains, and the remains of once-living plants and animals, that have been moved by water, ice or gravity
15.
sedimentary rock: forms when sediments are compacted and cemented together or when minerals form from solutions
