A set of words, numbers, locations, or other data put into a computer program. Data bases are set up so that related pieces of information can be easily retrieved and compiled.
An isotope produced by decay of a radioactive element.
A type of landslide made up of a mixture of water-saturated rock debris and soil with a consistency similar to wet cement. Debris flows move rapidly downslope under the influence of gravity. Sometimes referred to as earth flows or mud flows.
Removal of loose material by wind.
General term for folding, faulting, and other processes resulting from shear, compression, and extension of rocks.
A fan-shaped deposit that forms where a stream enters a lake or ocean and drops its load of sediment.
The weight per unit volume of a material.
A region with an average annual rainfall of 10 inches or less.
A gray or reddish-brown layer on rock
surfaces that darkens and thickens with increasing age. Desert varnish results from microbial
life processes that precipitate thin skins of clays and manganese oxide minerals.
The thicknesses can be used to determine the amount of time the surface of a rock has been
Any accumulation of sediment.
A closely-packed surface layer of coarse pebbles and gravel.
To dry out, usually by evaporation of water.
A group of processes that cause physical and chemical changes in sediment after it has been deposited and buried under another layer of sediment. Diagenesis may culminate in lithification of sediment, turning it into solid rock.
Forceful, upward intrusion of a rock mass into overlying rock. In the case of an igneous diapir, the intruding rock may be magma or a crystal-rich mush, either of which is less dense than the surrounding rock.
A sheet-like or tabular-shaped igneous intrusion that cuts across the sedimentary layering, metamorphic foliation, or other texture of a pre-existing rock.
Intrusive igneous rock made of plagioclase feldspar and amphibole and/or pyroxene. Similar to gabbro only not as so dark, and containing less iron and magnesium.
A measure of the angle between the flat horizon and the slope of a sedimentary layer, fault plane, metamorphic foliation, or other geologic structure.
In karst areas, streams often disappear into the ground usually at a sinkhole.
The amount of water issuing from a spring or in a stream that passes a specific point in a given period of time.
The process of chemical weathering of bedrock in which the combination of water and acid slowly removes mineral compounds from solid bedrock and carries them away in liquid solution. Also called chemical solution.
A boundary in which two tectonic plates move apart.
Any channel that carries water.
The land area drained by a stream.
A magnesium-rich carbonate sedimentary rock. Also, a magnesium-rich carbonate mineral (CaMgCO3)
A usually asymmetrical hill of wind-deposited sand.
An outer rind or crust formed on a rock. Durable crusts form when rock chemically reacts with water and possibly atmospheric dust, producing a hard outer surface that resists weathering.