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Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains, cemented together by another mineral. Sandstones comprise about 20–25% of all sedimentary rocks. [1] Most sandstone is composed of quartz or feldspar, because they are the most resistant minerals to the weathering processes at the Earth's ...
A quartz arenite or quartzarenite is a sandstone composed of greater than 90% detrital quartz. [1] Quartz arenites are the most mature sedimentary rocks possible, and are often referred to as ultra- or super-mature, and are usually cemented by silica. They often exhibit both textural and compositional maturity.
Quartz is, therefore, classified structurally as a framework silicate mineral and compositionally as an oxide mineral. Quartz is the second most abundant mineral in Earth's continental crust, behind feldspar. [10] Quartz exists in two forms, the normal α-quartz and the high-temperature β-quartz, both of which are chiral. The transformation ...
As first demonstrated in the 1979 paper by Bill Dickinson and Chris Suczek, [1] the composition and provenance of a sandstone is directly related to its tectonic environment of formation. Craton sands are clustered near the Q pole. As sandstones, these are known as quartz arenites. Transitional continental sands are along the QF line.
Very fine sandstone: chert-cemented submature quartzose phyllarenite ... Cements are authigenic minerals precipitated in the pores of clastic rocks. The composition ...
Quartzite is a very hard rock composed predominantly of an interlocking mosaic of quartz crystals. The grainy, sandpaper-like surface is glassy in appearance. Minor amounts of former cementing materials, iron oxide, silica, carbonate and clay, often migrate during recrystallization, causing streaks and lenses to form within the quartzite. [ 1 ]
A ganister (or sometimes gannister [1]) is hard, fine-grained quartzose sandstone, or orthoquartzite, [2] used in the manufacture of silica brick typically used to line furnaces. Ganisters are cemented with secondary silica and typically have a characteristic splintery fracture.
The Gog Group consists primarily of thick deposits of cross-bedded quartzose sandstone and quartzite, with minor quartzitic conglomerate and sub-arkosic sandstone. It also includes mudstone, siltstone, limestone and dolomite formations.