Stromatoporoids as Reef Constructors
at Wawautosa, Wisconsin

Detail of stromatoporoids, which appear as ribbon-like areas in the rock. Stromatoporoids are an extinct type of sponge, and the intergrowth of their skeletons trapped and bound carbonate mud, helping to build the reef structure.

Polished slab showing stromatoporoids (white to light brown) and carbonate mud (grey-green).

© 1997, Milwaukee Public Museum, Inc.