Tightly packed round to sub-round microbialites.Microbialites in zone 1 are stromatolitic, have diameters of between 10 to 30 cm at their longer axes, and are typically 20–40 cm tall. Synoptic relief is about 10–20 cm. The interspace material is an intra-bioclastic grainstone with some minor packstone domains. Allochems, predominantly composed of
intraclasts (50%) and trilobite bioclasts (40%), average 0.5–4 mm in length, appear moderately sorted, sub-rounded, but generally are not
spherical. Some trilobite bioclasts are over 1 cm long. Zone 1 microbialites have a small areal distribution of about 1 km2. Microbialites in zone 2, which cover the majority of the bed,
are also stromatolitic, have diameters that vary from 40 to 70 cm across their longer axes, and have heights that fluctuate from a few dm to about 70 cm. Synoptic relief is about 10–20 cm. The interspace material is an intrabioclastic grainstone with some minor packstone domains. Allochems, predominantly composed of intraclasts (70%) and trilobite bioclasts (20%) average 0.5–2 mm in length, appear well-sorted, well-rounded, and are sub-spherical. These microbialites are chiefly differentiated from those in zone 1 by the presence of a central core composed of mini-stromatolites. Sponges are recognized as spicule networks that typically do not exceed a few cm in size, with many not exceeding 1 cm