o Sandstone
Forms in a variety of environments - beaches, dunes, offshore continental margins.
Sorting: range of particle sizes; reflects mode of deposition.
well sorted - small range; well "worked"
poorly sorted - large range; not "worked"
Rounding: particles have absence of sharp corners, are well worked or have been transported a long distance.
Quartz sandstone (very common) = quartz
Arkose = quartz + feldspar (± mica)
Graywacke (submarine) = quartz + feldspar + clay + rock fragments + mafic minerals.