Information AboutSand |
| CATEGORIES ABOUT SAND | |
| granular materials | |
| pedology | |
| sediments | |
| sedimentology | |
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in the sand]] Sand is an example of a class of materials called , with particles ranging up to 64 mm (see Grain Size for standards in use). Sand feels gritty when rubbed between your fingers (silt feels like flour). CONSTITUENTS OF SAND The most common constituent of sand in inland continental settings and non- Tropical coastal settings is Silica (silicon dioxide), usually in the form of Quartz which because of its chemical inertness and considerable hardness is quite resistant to Weathering . However, the composition of sand varies according to local rock sources and conditions. The bright White Sands found in tropical and subtropical coastal settings are ground-up Limestone . Arkose is a sand or Sandstone with considerable Feldspar content which is derived from the Weathering and Erosion of a usually nearby Granite . Some locations have sands that contain Magnetite , Chlorite , Glauconite , or Gypsum . Sands rich in magnetite are dark to black in color, as are sands derived from volcanic basalts. The chlorite-glauconite bearing sands are typically green in color, as are sands derived from basalts ( Lava s) with a high Olivine content. The gypsum sand dunes of the White Sands National Monument in New Mexico are famous for their bright, white color. Sand deposits in some areas contain Garnet s and other resistant minerals, including some small Gemstone s. PHYSICAL ATTRIBUTES The volume of a grain of Quartz sand with a diameter of 0.060 mm (a lower bound) is 1.13 x 10-13 m3 with a mass of 3.00 x 10-13 g. As an upper bound, the volume and mass of a grain of sand with a diameter of 2.10 mm are 4.85 x 10-9 m3 and 1.28 x 10-8 g. {Link without Title} TRANSPORT Sand is transported by Wind or Water and deposited in the form of Beach es, Dune s, Sand Spits , Sand Bars , and the like. In most Deserts , sand is a dominant constituent of the soil. STUDY OF SAND The study of sand is called Arenology . Study of individual grains can reveal quite a bit of historical information as to the origin, kind of transport, etc of the grain. Quartz sand that is recently weathered from Granite or Gneiss quartz crystals will be angular. It is called ''sharp sand'' in the building trade where it is preferred for concrete mixing, and in gardening where it is used as a soil amendment to loosen clay soils. Sand that is Erosion transported long distances by water or wind will be rounded, with characteristic abrasion patterns on the surface of the grains. USES OF SAND Sand is often a principal component of the aggregate used in the preparation of Concrete . Sand manufactured at rock crusher plants for use as an aggregate is called '' Mansand ''. Graded sand is used as an Abrasive in Sandblasting and is also used in Media Filter s for filtering Water . Brick Manufacturing Plant s use sand as an additive with a mixture of Clay and other materials for manufacturing bricks. Sand is also sometimes mixed with Paint to create a textured finish for walls and ceilings or a non-slip surface. Sandy Soil s are ideal for certain crops such as Watermelon s, Peach es, and Peanut s and are often preferred for intensive Dairy Farming because of their excellent drainage characteristics. Sand is used in Landscaping , it is added to make small hills and slopes (e.g. for making Golf courses). Sand is the principal component in Glass manufacturing. Sandbag s are used for protection against Flood s and Gun fire. They can be easily transported when empty, and filled with local sand. People, especially Children , love to Play with sand on a Beach or in a Sandpit . Sometimes they build sand castles. See Sand Art And Play for details. HAZARDS OF SAND While sand is generally harmless, one must take care with some activities involving sand such as Sandblasting . Bags of silica sand now typically carry labels warning the user to wear respiratory protection and avoid breathing the fine silica dust because of this. There have been a number of lawsuits in recent years where workers have sought damages after they developed Silicosis , a Lung Disease caused by inhalation of fine silica particles over long periods of time. Material Safety Data Sheet s (MSDS) for silica sand state that "excessive inhalation of crystalline silica is a serious health concern" {Link without Title} . Sand 'mining' People have been severely injured and even killed after digging sand "caves" in large dunes, sandhills, or even on beaches when the cave or tunnel collapsed upon them. SEE ALSO |
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