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In oceanography, terrigenous sediments are those derived from the erosion of rocks on land; that is, they are derived from terrestrial (as opposed to marine) environments. [1] Consisting of sand , mud , and silt carried to sea by rivers , their composition is usually related to their source rocks; deposition of these sediments is largely ...
Economic geology is concerned with earth materials that can be used for economic and industrial purposes. These materials include precious and base metals, nonmetallic minerals and construction-grade stone. Economic geology is a subdiscipline of the geosciences; according to Lindgren (1933) it is “the application of geology”.
Authigenesis is the process whereby a mineral or sedimentary rock deposit is generated where it is found or observed. Such deposits are described as authigenic . Authigenic sedimentary minerals form during or after sedimentation by precipitation or recrystallization as opposed to detrital minerals, which are weathered by water or wind and ...
In ore deposit geology, hypogene processes occur deep below the Earth's surface, and tend to form deposits of primary minerals, as opposed to supergene processes that occur at or near the surface, and tend to form secondary minerals. [1] At great depth the pressure is high, and water can remain liquid at temperatures well above 100 °C.
The sediment can consist of terrigenous material, which originates on land, but may be deposited in either terrestrial, marine, or lacustrine (lake) environments, or of sediments (often biological) originating in the body of water. Terrigenous material is often supplied by nearby rivers and streams or reworked marine sediment (e.g. sand). In ...
In economics, land comprises all naturally occurring resources as well as geographic land. Examples include particular geographical locations, mineral deposits, forests, fish stocks, atmospheric quality, geostationary orbits, and portions of the electromagnetic spectrum. Supply of these resources is fixed. [1]
Experts say vehicle-based attacks are simple for a 'lone wolf' terrorist to plan and execute, and challenging for authorities to prevent.
Manganese nodule Nodules on the seabed Ferromanganese nodules found on the seafloor. Polymetallic nodules, also called manganese nodules, are mineral concretions on the sea bottom formed of concentric layers of iron and manganese hydroxides around a core.