360 m thick reef.
Main framework builders: Fistulella (problematic hydrozoan), stromatoporoids (Clatrodyction, Columnostroma), rugose corals, Spongophylloides, Zelolasma, Aphyllum, Solenopora, Parachaetetes, Renalcis, Epiphyton, Girvanella, Ikella. 

Rich in brachiopods