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Additionally, chalk is the only form of limestone that commonly shows signs of compaction. [8] Flint (a type of chert) is very common as bands parallel to the bedding or as nodules in seams, or linings to fractures, embedded in chalk. It is probably derived from sponge spicules [4] or other siliceous organisms as water is expelled upwards ...
The products of chalk weathering are dissolved in rainwater and are transported in stream flow. Chalk streams transport little suspended material (unlike most rivers), but are considered "mineral-rich" due to the dissolved calcium and carbonate ions. The surface water of chalk streams is commonly described as "gin clear".
The Chalk Group is now divided into a White Chalk Subgroup and a Grey Chalk Subgroup, both of which are further subdivided into formations. These modern divisions replace numerous earlier divisions, references to which occur widely on geological maps and in other geological literature.
Water treatment is any process that is used to remove contaminants from water and to improve the quality of water. Treated water can be allocated as drinking water for households, supply for industrial or agricultural use and the treatment method depends on the purpose of the end-use. Also, water treatment is used to safely return water to the ...
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The chalk formation of the hills provides exceptionally good drainage, with the result that most of these valleys are dry; indeed, surface water is quite scarce throughout the Wolds. Typically the valleys are hard to see from above, creating the visual impression that the landscape is much flatter than is actually the case.
The Cretaceous is justly famous for its chalk; indeed, more chalk formed in the Cretaceous than in any other period in the Phanerozoic. [27] Mid-ocean ridge activity—or rather, the circulation of seawater through the enlarged ridges—enriched the oceans in calcium ; this made the oceans more saturated, as well as increased the ...
Water is the medium of the oceans, the medium which carries all the substances and elements involved in the marine biogeochemical cycles. Water as found in nature almost always includes dissolved substances, so water has been described as the "universal solvent" for its ability to dissolve so many substances.