Siliciclastic rocks (commonly misspelled siliclastic) are clastic noncarbonate sedimentary rocks that are almost exclusively silica-bearing, either as forms of quartz or other silicate minerals. All siliciclastic rocks are formed by inorganic processes, or deposited through some mechanical process, such as stream deposits (delta deposits) that are subsequently lithified. They are sandstone based rocks accounting for about 50 - 60% of the world oil and gas exploration. The other silicate minerals that are generally present in siliciclastic sedimentary rocks are feldspar, biotite, etc....
Siliciclastic sediments are silica-based sediments, lacking carbon compounds, which are formed from pre-existing rocks, by breakage, transportation and redeposition to form sedimentary rock.