Upper Devonian (ILDu;0)

State	Illinois
Name	Upper Devonian
Geologic age	Devonian
Original map label	5810
Comments	The upper Devonian includes the following formations: Louisiana Limestone, Saverton Shale, Grassy Creek Shale, Sweetland Creek Shale, Sylamore Sandstone. Based on the stratigraphic column on the 1967 paper map, these units together are about 10% sandstone, 20 % limestone, 40% shale, and 30% black shale.
Primary rock type	shale
Secondary rock type	black shale
Other rock types	limestone; sandstone
Lithologic constituents	Major Sedimentary > Clastic > Mudstone > Shale > Black-shaleThe upper Devonian includes the following formations: Lousiana Limestone, Saverton Shale, Grassy Creek Shale, Sweetland Creek Shale, Sylamore Sandstone. Based on the stratigraphic column on the 1967 paper map, these units together are about 10% sandstone, 20 % limestone, 40% shale, and 30% black shale Minor Sedimentary > Clastic > Mudstone > ShaleThe upper Devonian includes the following formations: Lousiana Limestone, Saverton Shale, Grassy Creek Shale, Sweetland Creek Shale, Sylamore Sandstone. Based on the stratigraphic column on the 1967 paper map, these units together are about 10% sandstone, 20 % limestone, 40% shale, and 30% black shale Sedimentary > Carbonate > LimestoneThe upper Devonian includes the following formations: Lousiana Limestone, Saverton Shale, Grassy Creek Shale, Sweetland Creek Shale, Sylamore Sandstone. Based on the stratigraphic column on the 1967 paper map, these units together are about 10% sandstone, 20 % limestone, 40% shale, and 30% black shale Sedimentary > Clastic > SandstoneThe upper Devonian includes the following formations: Lousiana Limestone, Saverton Shale, Grassy Creek Shale, Sweetland Creek Shale, Sylamore Sandstone. Based on the stratigraphic column on the 1967 paper map, these units together are about 10% sandstone, 20 % limestone, 40% shale, and 30% black shale.
Map references	Willman, H.B., and others, (compilers), 1967, Geologic Map of Illinois: Illinois State Geological Survey, scale= 1:500,000, paper.
Unit references	Willman, H.B., and others, (compilers), 1967, Geologic Map of Illinois: Illinois State Geological Survey, scale= 1:500,000, paper.
Geographic coverage	Adams - Alexander - Calhoun - Champaign - Cook - Douglas - Ford - Greene - Hardin - Henderson - Henry - Iroquois - Jersey - McLean - Mercer - Piatt - Pike - Pulaski - Rock Island - Scott - Union - Vermilion - Warren