Search results
Results from the WOW.Com Content Network
Calcareous soils are relatively alkaline, in other words they have a high pH.They are characterized by the presence of calcium carbonate in the parent material; the carbonate-ion is a base.
Caliche fossil forest on San Miguel Island, California. Caliche (/ k ə ˈ l iː tʃ iː /) (unrelated to the street-slang "Caliche" spoken in El Salvador) is a soil accumulation of soluble calcium carbonate at depth, where it precipitates and binds other materials—such as gravel, sand, clay, and silt.
[4] [3] The remaining carbonate rock is mostly dolomite, a closely related rock, which contains a high percentage of the mineral dolomite, CaMg(CO 3) 2. Magnesian limestone is an obsolete and poorly-defined term used variously for dolomite, for limestone containing significant dolomite ( dolomitic limestone ), or for any other limestone ...
It is a common substance found in rocks as the minerals calcite and aragonite, most notably in chalk and limestone, eggshells, gastropod shells, shellfish skeletons and pearls. Materials containing much calcium carbonate or resembling it are described as calcareous .
Marl has been used as a soil conditioner and neutralizing agent for acid soil [13] [17] and in the manufacture of Portland cement. [18] Because some marls have a very low permeability , they have been exploited for construction of the Channel Tunnel between England and France and are being investigated for the storage of nuclear waste .
The following is a list of rock types recognized by geologists.There is no agreed number of specific types of rock. Any unique combination of chemical composition, mineralogy, grain size, texture, or other distinguishing characteristics can describe a rock type.
Tufa columns at Mono Lake, California. Tufa is a variety of limestone formed when carbonate minerals precipitate out of water in unheated rivers or lakes. Geothermally heated hot springs sometimes produce similar (but less porous) carbonate deposits, which are known as travertine or thermogene travertine.
A Calcisol in the World Reference Base for Soil Resources (WRB) [1] is a soil with a substantial secondary accumulation of lime. Calcisols are common in calcareous parent materials and widespread in arid and semi-arid environments. Formerly Calcisols were internationally known as Desert soils and Takyrs.