The Dunham classification system for carbonate sedimentary rocks was originally devised by Robert J. Dunham in 1962,[1] and subsequently modified by Embry and Klovan in 1971[2] to include coarse-grained limestones and sediments that had been organically bound at the time of deposition. The modified Dunham Classification has subsequently become the most widely employed system for the classification of carbonate sedimentary rocks with 89%[3] of workers currently adopting this system over the alternative Folk[4] classification scheme