Fig. 11--Photomicrographs of Black River textures.

1. Mud/wackestone with scattered brachiopod and crinoid fragments. Silt-size quartz is also present. PPL. Sun Bradley No. 4, 6373 ft.

2. Shaly mudstone with abundant dolomite rhombs. CN. Humble Riley No. 2, 4228 ft.

3. Scattered dolomite rhombs in a bryozoan-rich wackestone. PPL. Humble Riley No. 2, 4216 ft.

4. Peloid-rich crinoidal wacke/packstone. PPL. Humble Riley No. 2, 4216 ft.

5. Fractured peloidal packstone. Dolomite (to the right) is concentrated in a burrow. PPL. Consumers Power Co. No. 210, 4429 ft.

6. Xenotopic dolomite with minor amounts of intercrystalline porosity. Original texture was probably a wackestone. PPL. Carter Lauber No. 12, 5200 ft.