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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.
A QFL chart is a representation of the framework grains and matrix that is present in a sandstone. This chart is similar to those used in igneous petrology. When plotted correctly, this model of analysis creates a meaningful quantitative classification of sandstones. [24] A sandstone provenance chart is typically based on a QFL chart but allows ...
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.
The other three properties should always be mentioned. The following are examples of rock names using Folk's fivefold name: Coarse sandstone: calcitic submature micaceous subarkose Fine sandstone: supermature quartzarenite Sandy granule conglomerate: calcitic submature calclithite Very fine sandstone: chert-cemented submature quartzose phyllarenite
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 ...
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.
QAPF diagrams are not used if mafic minerals make up more than 90% of the rock composition (for example: peridotites and pyroxenites). Instead, an alternate triangle plot diagram is used; (see Streckeisen diagram, lower right.) An exact name can be given only if the mineralogical composition is established, which cannot be determined in the field.
Evaporite – Water-soluble mineral deposit formed by evaporation from an aqueous solution; Flint – Cryptocrystalline form of the mineral quartz; Geyserite – Form of opaline silica often found around hot springs and geysers; Greywacke – Sandstone with angular grains in a clay-fine matrix; Gritstone – Hard, coarse-grained, siliceous ...