It is widely believed that the formation originally deposited on a shallow rimmed shelf, followed by the development of barrier reefs into an nonlinear and uncoordinated "belt" around the Hudson Basin. Within the
Hudson Bay Lowlands, the formation consists of
dolomite and
limestone rich in both coral and sponge. The formation is a haven for
lithotopes, or media for sediments to deposit, with various types including: • Mottled to Nodular Skeletal Wackestone • Stromatoporoid-Coral Framestone • Pelodial Intraclastic Bindstone • Graded Oolitic Grainstone The formation's depth reaches 62 meters at its deepest. ==Fossil content==