Editing Sedimentary rock (section)

====Sandstones====
[[File:Sedimentgesteine auf Malta.JPG|thumb|upright=1.1|Sedimentary rock with sandstone in [[Malta]], southern Europe]]
[[File:Lower antelope 3 md.jpg|thumb|upright=1.2|[[Lower Antelope Canyon]] was carved out of the surrounding [[sandstone]] by both mechanical weathering and chemical weathering. Wind, sand, and water from [[flash flood]]ing are the primary weathering agents.]]
{{main|Sandstone}}

Sandstone classification schemes vary widely, but most geologists have adopted the Dott scheme,{{sfn|Dott|1964}} which uses the relative abundance of quartz, feldspar, and lithic framework grains and the abundance of a muddy matrix between the larger grains.

:''Composition of framework grains''
:The relative abundance of sand-sized framework grains determines the first word in a sandstone name. Naming depends on the dominance of the three most abundant components quartz, feldspar, or the lithic fragments that originated from other rocks. All other minerals are considered accessories and not used in the naming of the rock, regardless of abundance.

::* Quartz sandstones have >90% quartz grains
::* Feldspathic sandstones have <90% quartz grains and more feldspar grains than lithic grains
::* Lithic sandstones have <90% quartz grains and more lithic grains than feldspar grains

:''Abundance of muddy matrix material between sand grains''
::When sand-sized particles are deposited, the space between the grains either remains open or is filled with mud (silt and/or clay sized particle).
::* "Clean" sandstones with open pore space (that may later be filled with matrix material) are called arenites.
::* Muddy sandstones with abundant (>10%) muddy matrix are called wackes.

Six sandstone names are possible using the descriptors for grain composition (quartz-, feldspathic-, and lithic-) and the amount of matrix (wacke or arenite). For example, a quartz arenite would be composed of mostly (>90%) quartz grains and have little or no clayey matrix between the grains, a lithic wacke would have abundant lithic grains and abundant muddy matrix, etc.

Although the Dott classification scheme{{sfn|Dott|1964}} is widely used by sedimentologists, common names like [[greywacke]], [[arkose]], and quartz sandstone are still widely used by non-specialists and in popular literature.