Stratigraphy of the Carbondale and McLeansboro Groups in Southwestern Indiana

Middle and Upper Pennsylvanian rocks in Southwestern Indiana were studied using outcrops, cores, driller's logs of core tests, and electric logs of oil tests. These rocks are sedimentary in origin. Clastic rocks--sandstone, shale, and mudstone--comprise 95 percent of the volume. Limestone makes up nearly two percent, coal is nearly three percent and minor amounts of chert and ironstone are present. The group names Raccoon Creek, Carbondale, and McLeansboro are applied here in Indiana. The Carbondale group contains most of the thick coals. The McLeansboro group contains many thin coals and limestones.Indiana Department of Conservatio