Quartzarenite
Encyclopedia
A quartz arenite or quartzarenite is a sandstone
Sandstone
Sandstone is a sedimentary rock composed mainly of sand-sized minerals or rock grains.Most sandstone is composed of quartz and/or feldspar because these are the most common minerals in the Earth's crust. Like sand, sandstone may be any colour, but the most common colours are tan, brown, yellow,...

 composed of greater than 90% detrital
Detrital
Detritus is a geological term used to describe particles of rock derived from pre-existing rock through processes of weathering and erosion. Detrital particles can consist of lithic fragments , or of monomineralic fragments...

 quartz
Quartz
Quartz is the second-most-abundant mineral in the Earth's continental crust, after feldspar. It is made up of a continuous framework of SiO4 silicon–oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall formula SiO2. There are many different varieties of quartz,...

, with limited amounts of other framework grains (feldspar
Feldspar
Feldspars are a group of rock-forming tectosilicate minerals which make up as much as 60% of the Earth's crust....

, lithic fragments, etc.) and matrix
Matrix (geology)
The matrix or groundmass of rock is the finer grained mass of material in which larger grains, crystals or clasts are embedded.The matrix of an igneous rock consists of finer grained, often microscopic, crystals in which larger crystals are embedded. This porphyritic texture is indicative of...

. It can have higher-than-average amounts of resistant grains, like chert
Chert
Chert is a fine-grained silica-rich microcrystalline, cryptocrystalline or microfibrous sedimentary rock that may contain small fossils. It varies greatly in color , but most often manifests as gray, brown, grayish brown and light green to rusty red; its color is an expression of trace elements...

 and minerals in the ZTR index
ZTR index
The ZTR index is a method of determining how weathered, both chemically and mechanically, a sediment is. The letters in ZTR stand for 3 common minerals found in ultra-weathered sediments: zircon, tourmaline, and rutile...

.

The term 'quartz arenite' is derived from the main component (quartz) and arenite
Arenite
Arenite is a sedimentary clastic rock with sand grain size between 0.0625 mm and 2 mm and contain less than 15% matrix. The related adjective is arenaceous...

, a Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...

 term for a rock with sand
Sand
Sand is a naturally occurring granular material composed of finely divided rock and mineral particles.The composition of sand is highly variable, depending on the local rock sources and conditions, but the most common constituent of sand in inland continental settings and non-tropical coastal...

-sized grains. In some literature, these can be called orthoquartzites, a confusing term which usually refers to the metamorphic rock
Metamorphic rock
Metamorphic rock is the transformation of an existing rock type, the protolith, in a process called metamorphism, which means "change in form". The protolith is subjected to heat and pressure causing profound physical and/or chemical change...

 quartzite
Quartzite
Quartzite is a hard metamorphic rock which was originally sandstone. Sandstone is converted into quartzite through heating and pressure usually related to tectonic compression within orogenic belts. Pure quartzite is usually white to gray, though quartzites often occur in various shades of pink...

, though most metamorphic quartzites are diagentically fused from quartz arenites. The term "quartzose sandstone" can also be used for a quartz arenite.

Quartz arenites are the most mature
Maturity (sedimentology)
In sedimentology, maturity describes the composition of grains in sandstones occurring from various amounts of sediment transportation. It occurs when the grains in a sediment become well-sorted and well-rounded due to weathering of the grains...

 sedimentary rock
Sedimentary rock
Sedimentary rock are types of rock that are formed by the deposition of material at the Earth's surface and within bodies of water. Sedimentation is the collective name for processes that cause mineral and/or organic particles to settle and accumulate or minerals to precipitate from a solution....

s 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 two primary sedimentary depositional environment
Sedimentary depositional environment
In geology, sedimentary depositional environment describes the combination of physical, chemical and biological processes associated with the deposition of a particular type of sediment and, therefore, the rock types that will be formed after lithification, if the sediment is preserved in the rock...

s that produce quartz arenites are beach
Beach
A beach is a geological landform along the shoreline of an ocean, sea, lake or river. It usually consists of loose particles which are often composed of rock, such as sand, gravel, shingle, pebbles or cobblestones...

es/upper shoreface
Upper shoreface
Upper Shoreface refers to the portion of the seafloor that is shallow enough to be agitated by everyday wave action . Below that is lower shoreface.-Overview:...

 and aeolian processes, due to their high residence time, high transport distance, and/or high energy of the environment. Most of the time, these sediments are reworked over and over, even being eroded out of a lithified rock and becoming a brand new sediment and rock. This is known as a multicycle sand.
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