The Needles, situated on the Isle of Wight, are part of the extensive Southern England Chalk Formation. The Needles is a row of three distinctive stacks of Chalk that rise out of the Sea off the western extremity of the Isle of Wight, The Isle of Wight is an English Island and county in the English Channel between three and five miles (8 km from the south coast of the KentGeologyWealdenDomeSimplesvg|thumb|The Wealden Anticline]] The Chalk Formation of Southern England is a system of Chalk Downland in

Chalk (pronounced /ˈtʃɔːk/) is a soft, white, porous sedimentary rock, a form of limestone composed of the mineral calcite. Sedimentary rock is one of the three main rock types (the others being igneous and Metamorphic rock) Limestone is a Sedimentary rock composed largely of the Mineral Calcite ( Calcium carbonate: CaCO3 A mineral is a naturally occurring substance formed through geological processes that has a characteristic chemical composition a highly ordered atomic structure and specific Calcite is a carbonate mineral and the most stable polymorph of Calcium carbonate ( Ca[[carbon C]] O 3 It forms under relatively deep marine conditions from the gradual accumulation of minute calcite plates (coccoliths) shed from micro-organisms called coccolithophores. Calcite is a carbonate mineral and the most stable polymorph of Calcium carbonate ( Ca[[carbon C]] O 3 Coccoliths are individual plates of Calcium carbonate formed by Coccolithophores (single-celled algae such as Emiliania huxleyi Coccolithophores (also called coccolithophorids) are single-celled Algae, Protists and Phytoplankton belonging to the Division It is common to find flint and chert nodules embedded in chalk. Flint (or flintstone) is a hard sedimentary Cryptocrystalline form of the Mineral Quartz, categorized as a variety of Chert Chert (ˈtʃɝt is a fine-grained Silica -rich Microcrystalline, Cryptocrystalline or Microfibrous Sedimentary rock that may contain

Chalk is relatively resistant to erosion and slumping compared to the clays with which it is usually associated, thus forming tall steep cliffs where chalk ridges meet the sea. Erosion is the carrying away or displacement of solids ( Sediment, Soil, rock and other particles usually by the agents of currents such as wind Clay is a naturally occurring material composed primarily of fine-grained Minerals which show plasticity through a variable range of Water content, and In Geography and Geology, a cliff is a significant vertical or near vertical rock exposure Chalk hills, known as chalk downland, usually form where bands of chalk reach the surface at an angle, so forming a scarp slope. A downland is an area of open Chalk Hills This term is especially used to describe the Chalk countryside in southern England. In Geomorphology, an escarpment is a transition zone between different physiogeographic provinces that involves a sharp steep Elevation differential characterized Because chalk is porous it can hold a large volume of ground water, providing a natural reservoir that releases water slowly through dry seasons. Groundwater is Water located beneath the Ground surface in Soil pore spaces and in the Fractures of lithologic formations

Chalk has been quarried since prehistory, providing building material and marl for fields. Marl or Marlstone is a Calcium carbonate or lime -rich mud or Mudstone which contains variable amounts of Clays and Aragonite In southeast England, deneholes are a notable example of ancient chalk pits. England is a Country which is part of the United Kingdom. Its inhabitants account for more than 83% of the total UK population whilst its mainland A Denehole (alternatively Dene hole or Dene-hole) is an underground structure consisting of a number of small chalk caves entered by a vertical shaft

The Chalk Formation is a European stratigraphic unit deposited during the late Cretaceous Period. The Chalk Formations of Europe are thick deposits of Chalk, a soft porous white Limestone, deposited in a marine environment during the upper Cretaceous The Cretaceous (kriːˈteɪʃəs, usually abbreviated 'K' for its German translation "Kreide" is a geologic period and system, reaching from the end of It forms the famous White Cliffs of Dover in Kent, England. The white cliffs of Dover are Cliffs which form part of the British coastline facing the Strait of Dover and France. KENT (1400 AM) is a Radio station broadcasting a Adult Standards/MOR format England is a Country which is part of the United Kingdom. Its inhabitants account for more than 83% of the total UK population whilst its mainland The Champagne region of France is mostly underlain by chalk deposits, which contain famous caves beneath the hills. The Champagne wine region ( archaic Champany is a historic province within the Champagne administrative province in the northeast of France. This article is about the country For a topic outline on this subject see List of basic France topics.

Chalk uses

The traditional uses of chalk have in many cases been replaced by other substances, although the word "chalk" is often still applied to the replacements.

• Blackboard chalk is a substance used for drawing on rough surfaces, as it readily crumbles leaving particles that stick loosely to these surfaces. A chalkboard or blackboard is a reusable Writing surface on which text or drawings are made with sticks of Calcium sulfate, known when used for this Although traditionally composed of natural chalk, modern blackboard chalk is generally made from the mineral gypsum (calcium sulfate), often supplied in sticks of compressed powder about 10 cm long. Gypsum is a very soft Mineral composed of Calcium sulfate dihydrate with the Chemical formula Ca[[sulfur S]] O 4·2 Calcium sulfate is a common laboratory and industrial chemical A centimetre ( American spelling: centimeter, symbol cm) is a unit of Length in the Metric system, equal to one hundredth

• In agriculture chalk is used for raising pH in soils with high acidity. Agriculture refers to the production of goods through the growing of plants and fungi and the raising of domesticated Animals The study of agriculture pH is the measure of the acidity or alkalinity of a Solution. In Computer science, ACID ( Atomicity Consistency Isolation Durability) is a set of properties that guarantee that Database transactions are The most common forms are CaCO₃ (Calcium carbonate) and CaO (Calcium Oxide). Calcium carbonate is a Chemical compound with the Chemical formula Ca[[Carbon C]] O 3 Calcium oxide ( CaO) commonly known as burnt lime, lime or quicklime, is a widely used Chemical compound.

• In lawn tennis, powdered chalk was used to mark the boundary lines of the court. Tennis is a sport played between two players ( singles) or between two teams of two players each ( doubles) This gives the advantage that, if the ball hits the line, a cloud of chalk or pigment dust can be seen. Nowadays the substance used is mostly titanium dioxide. Titanium dioxide, also known as titanium(IV oxide or titania, is the naturally occurring Oxide of Titanium, chemical formula Ti[[oxygen

• In gymnastics, rock-climbing, bouldering, weight-lifting and tug of war, chalk—now usually magnesium carbonate—is applied to the hands to prevent slipping. Gymnastics is a Sport involving performance of exercises requiring physical strength agility and coordination Rock climbing is a Sport in which participants climb up or across natural rock formations or man-made rock walls with the goal of reaching the Bouldering is a style of Rock climbing undertaken without a rope and normally limited to very short climbs so that a fall will not result in serious injury Weightlifting, also called Olympic weightlifting or Olympic-style weightlifting, is a sport in which participants attempt a maximum weight single lift of a barbell Tug of war, tug o' war, or tug war, also known as rope pulling, is a Sport that directly puts two teams against each other in a test of strength Magnesium carbonate, MgCO3 is a white Solid that occurs in nature as a Mineral.

• Tailor's chalk is traditionally a hard chalk used to make temporary markings on cloth, mainly by tailors. Nowadays it is usually made from talc (magnesium silicate). Talc (derived from the Persian via Arabic talq) is a Mineral composed of Hydrated Magnesium Silicate with Magnesium (mægˈniːziəm is a Chemical element with the symbol Mg, Atomic number 12 Atomic weight 24 For the Artificial intelligence Androids of the 1990s Science fiction series Space Above and Beyond, see Silicate (AI

• Sidewalk chalk is made of sticks of colored (and sometimes white) chalk (now mostly gypsum) used to draw on sidewalks, streets, and driveways. Julian Beever Mountain Dew art photo by David Shankbonejpg|thumb| Mountain Dew advertisement in Union Square, New York City by Julian Beever. It is often done by children, but in many cities, talented adult artists create masterpieces on the walkways.

• Toothpaste also commonly contains small amounts of chalk. Toothpaste is a Paste or Gel Dentifrice used to clean and maintain the aesthetics and health of Teeth.

See also

• Chalk carving
• Hill figure
• Pastel
• French chalk

External links

• Chalk cliffs in the North of Ireland
• Chalk: Sedimentary rocks