Black River Limestone (MIObr;0)

State	Michigan
Name	Black River Limestone
Geologic age	Late Ordovician
Original map label	Obr
Primary rock type	limestone
Secondary rock type
Other rock types
Lithologic constituents	Major Sedimentary > Carbonate > Limestone (Bed)
Map references	Reed, Robert C., and Daniels, Jennifer (compilers), 1987, Bedrock geology of northern Michigan: Geological Survey Division, Michigan Dept. of Natural Resources, scale= 1:500,000
Unit references	Reed, Robert C., and Daniels, Jennifer (compilers), 1987, Bedrock geology of northern Michigan: Geological Survey Division, Michigan Dept. of Natural Resources, scale= 1:500,000
Geographic coverage	Alger - Chippewa - Delta - Luce - Marquette - Menominee - Schoolcraft