Sponge-microbial boundstone composed primarily of spiculitic clots embedded in a detrital carbonatematrix The mound was buried by foreshoal grainstone, much of which is brecciated. Upper Tuscumbia bryozoan-crinoid grainstone formed in a mobile shoal that quickly aggraded to sea level. Echinoderm debris, brachiopods and bryozoans are  abundant. Rugose corals, trilobites, ostracods, and sponges are less common