Sandstone

Sandstone is a <a href="/facts/Clastic_rock/3y4SoUxl">clastic sedimentary rock</a> composed mainly of <a href="/facts/Grain_size/0jzacuSU">sand-sized</a> (0.0625 to 2 mm) <a href="/facts/Silicate_mineral/WclrQW2I">silicate</a> grains, <a href="/facts/Cementation_(geology)/gjsJHkBv">cemented</a> together by another mineral. Sandstones comprise about 20–25% of all <a href="/facts/Sedimentary_rock/HQDCjrco">sedimentary rocks</a>.
Most sandstone is composed of <a href="/facts/Quartz/4n86tE2G">quartz</a> or <a href="/facts/Feldspar/DVvFnfA9">feldspar</a>, because they are the most resistant <a href="/facts/Mineral/LkUFbNmv">minerals</a> to the <a href="/facts/Weathering/uSYGlv0H">weathering</a> processes at the Earth's surface. Like uncemented <a href="/facts/Sand/MdTIt0M8">sand</a>, sandstone may be imparted any color by impurities within the minerals, but the most common colors are tan, brown, yellow, red, grey, pink, white, and black. Because sandstone beds can form highly visible cliffs and other <a href="/facts/Topography/SS8Bx4t9">topographic</a> features, certain colors of sandstone have become strongly identified with certain regions, such as the red rock deserts of <a href="/facts/Arches_National_Park/1R5DhBCH">Arches National Park</a> and other areas of the <a href="/facts/Southwestern_United_States/LjLFs9fC">American Southwest</a>.
Rock formations composed of sandstone usually allow the <a href="/facts/Percolation/CRP2RCt6">percolation</a> of water and other fluids and are <a href="/facts/Porosity/UoyAJU8X">porous</a> enough to store large quantities, making them valuable <a href="/facts/Aquifer/UwG6ksdG">aquifers</a> and <a href="/facts/Petroleum_reservoir/wYoSQmGN">petroleum reservoirs</a>.
Quartz-bearing sandstone can be changed into <a href="/facts/Quartzite/8rNpCMrv">quartzite</a> through <a href="/facts/Metamorphism/8eWHgy6K">metamorphism</a>, usually related to tectonic compression within <a href="/facts/Orogenic_belts/XrvRMpsw">orogenic belts</a>.

Sandstone open-in-new

Sandstone