Abstract
The studied Triassic phosphorites are located in the Gharyan area, north-western Libya. The phosphorites form the lower part of the Abu Shaybah Formation and are composed of phosphate elements, such as pellets, micronodules, intraclasts, coprolites, and bone fragments, plus a mixture of carbonate and quartz grains. Petrographic study of the Gharyan Triassic phosphorites shows that they were formed by deposition as phosphate mud, followed by reworking and redeposition as phosphate sands.