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Chalk is so common in Cretaceous marine beds that the Cretaceous Period was named for these deposits. The name Cretaceous was derived from Latin creta, meaning chalk. [10] Some deposits of chalk were formed after the Cretaceous. [11] The Chalk Group is a European stratigraphic unit deposited during the late Cretaceous Period.
The crust formed on the lid was ground to powder and boiled with water to remove the calomel. Calx – calcium oxide; was also used to refer to other metal oxides. Chalcanthum – the residue produced by strongly roasting blue vitriol (copper sulfate); it is composed mostly of cupric oxide. Chalk – a rock composed of porous biogenic calcium ...
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".
Eventually the sea broke through river valleys in the North Downs to the south (Middle Chalk) and finally today's English Channel was opened up. [12] The proto-River Stour then formed part of the intervening water, with a new tributary, the River Wantsum, completing it; it became known as the Wantsum Channel.
Chalk is the rock type associated most closely with the National Park and, in common with the chalk which provides other key landscape features in the southeast of England, was formed by the settling to the sea floor of myriad coccoliths (microscopic plates of calcium carbonate formed by single-celled algae known as coccolithophores) during the Late Cretaceous epoch between about 100 and 70 ...
The term liquid chalk, or sharkchalk, refers to several different kinds of liquified chalk including liquid-chalk marking pens (with water-soluble ink), liquid-chalk mixtures (for athletic use: rock climbing, weightlifting, gymnastics), and liquid-chalk hobby-craft paints made of cornstarch and food coloring (some with small amounts of flour).
The chalk and water mixture, also called Kreidemilch or Kreidetrübe, was passed through separation tanks where the finer impurities, the Grand, settled out. The chalk suspension freed from the grand finally ended up in the settling basin, in which the still-suspended particles settled out and accumulated into a layer about 30 cm thick. The now ...
The name is derived from the Latin creta, 'chalk', which is abundant in the latter half of the period. It is usually abbreviated K, for its German translation Kreide. The Cretaceous was a period with a relatively warm climate, resulting in high eustatic sea levels that created numerous shallow inland seas.