| Stromatoporoid Biostrome: Large block of Cobleskill Limestone along the shore of Frontenac Island (note meter stick). In the very center (whitish area) is a favositid coral. The stromatoporoids are in relief due to dissolution of the limestone matrix by rainwaters (and probably lake waters during storms). |
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| STROMATOPOROID BIOSTROMES LATE SILURIAN COBLESKILL FORMATION FRONTENAC ISLAND, CAYUGA LAKE |