Small Shelly Fossils from the Middle Cambrian Stephen Formation, British Columbia, Canada  

In the Stanley Glacier area, Kootenay National Park (British Columbia, Canada), only the upper member (Waputik Member) of the Stephen Formation (Ehmaniella zone, Middle Cambrian) is present.  The member consists of six shale-dominated parasequences which grade upwards into pack- or grainstones.  It is underlain by cryptalgal laminites of the upper Cathedral Formation, and overlain by nodular carbonates of the Eldon Formation.  Fourteen carbonate horizons have been sampled for acetic acid preparation, ranging from the uppermost Cathedral Formation to the lowermost Eldon Formation.  Acid residues include common trilobites (e.g., Elrathina, Pagetia), inarticulate brachiopods (obolids, acrotretids, acrothelids, and paterinids), various morphologies of enigmatic sclerites (probably re-crystallized echinoderm ossicles), and internal molds of hyolith cones.  Helcionellids, sponge spicules, chancellorids, and bradoriids are present but rare.  The fauna and faunal associations vary with respect to stratigraphic position, and paleoenvironments inferred from sedimentological data.  Furthermore, the various inarticulate brachiopods, some of which were previously only known from shale preservation, display new details on shell structure and shell morphology.