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In geology, clay-with-flints is the name given by William Whitaker in 1861 to a peculiar deposit of stiff red, brown, or yellow clay containing unworn whole flints as well as angular shattered fragments, also with a variable admixture of rounded flint, quartz, quartzite, and other pebbles.
Soil contamination, soil pollution, or land pollution as a part of land degradation is caused by the presence of xenobiotic (human-made) chemicals or other alteration in the natural soil environment. It is typically caused by industrial activity, agricultural chemicals or improper disposal of waste .
Flint, occasionally flintstone, is a sedimentary cryptocrystalline form of the mineral quartz, [1] [2] categorized as the variety of chert that occurs in chalk or marly limestone. Historically, flint was widely used to make stone tools and start fires. Flint occurs chiefly as nodules and masses in sedimentary rocks, such as chalks and limestones.
A concretion is a hard and compact mass formed by the precipitation of mineral cement within the spaces between particles, and is found in sedimentary rock or soil. [1] Concretions are often ovoid or spherical in shape, although irregular shapes also occur.
Flint clays associated with coal typically occur as thin, laterally continuous layers (bands), called "tonsteins", found within coal beds. In the case of tonsteins found within coal, the formation of flint clays resulted from the alternation of glass comprising volcanic ash by acidic waters after it accumulated as thin beds within peat swamps ...
Groundwater pollution (also called groundwater contamination) occurs when pollutants are released to the ground and make their way into groundwater.This type of water pollution can also occur naturally due to the presence of a minor and unwanted constituent, contaminant, or impurity in the groundwater, in which case it is more likely referred to as contamination rather than pollution.
US News & World Report created a list of US cities with the best quality of life. The top locations include Honolulu and Ann Arbor, Michigan.
Layers vary from a few inches to feet thick, and multiple layers can exist in a single location. The caliche layer in a soil profile is sometimes called a K horizon. [2] [3] In northern Chile and Peru, caliche also refers to mineral deposits that include nitrate salts. [4] [5] Caliche can also refer to various claylike deposits in Mexico and ...