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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 Chalk Group (often just called the Chalk) is the lithostratigraphic unit (a certain number of rock strata) which contains the Upper Cretaceous limestone succession in southern and eastern England. The same or similar rock sequences occur across the wider northwest European chalk 'province'.
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 then collected in the settling basin, where the still- suspended particles settled out and accumulated into a layer about 30 cm thick.
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 Prairie Bluff Chalk is a geologic formation in Alabama and Mississippi.It preserves fossils dating back to the Cretaceous period. [2] [3]The chalk was formed by marine sediments deposited along the eastern edge of the Mississippi embayment during the Maastrichtian stage of the Late Cretaceous.
Dutch White – a pigment, formed from one part of white lead to three of barium sulfate. BaSO 4; Flowers of antimony – antimony trioxide, formed by roasting stibnite at high temperature and condensing the white fumes that form. Sb 2 O 3; Fool's gold – a mineral, iron disulfide or pyrite; can form oil of vitriol on contact with water and air.
The hills are formed from a series of pure marine limestones formed during the Cretaceous period, known collectively as the Chalk Group.The outcrop has the form of an arc running north from Ferriby on the Humber estuary west of Hull northwards past Market Weighton to the Malton area where it swings eastwards towards the North Sea coast between Filey and Bridlington.
The Dorset Downs are chalk hills formed by strata of the Chalk Group, a geological unit which also covers much of southern and eastern England. The chalk which comprises the downs was formed in the Cretaceous period, when the area now known as Dorset was below sea-level. The Dorset Downs are the largest outcrop of the chalk within Dorset, and ...