Sediment produced from abrasion of the branching stony coral Oculina Varicosa

Soft rubber tumbling barrels, some with screen windows, were used to simulate natural abrasionof coral branches. Tumbled for equal times, sealed barrrels produced more sediment from coral branchesthan barrels with windows, and dead coral produced more sediment than live coral. Tumbled dead coralproduced a gravel mode (2-4 mm) of fragmented barnacles and a sand mode (0.2 mm) of coral. Tumbledlive coral produced similar results but lacked barnacles. Time series tests of 1-1000 minutes showed thatclosed barrels produced increasingly greater percentages of carbonate mud and increasingly finer sand grainsizemodes. Tumbling barrels with screen windows yielded particles of unchanging size through the sameintervals. Natural sediment with broken coral branches contained coral sand most abundantly between0.125-0.250 mm, which is the same as produced by tumbling dead coral in barrels with screen windows.Strong grain-size modes at 0.2 mm produced by sonification and tumbling of live and dead coral in sealed and screen-window barrels support the Sorby Principle of skeletal breakdown.