Geologic image in the Kentucky Geological Survey data repository.Image Name: Black Shale, Monroe County Image Date: 5/22/2007 Category: photo_scene Source: Carey, Dan Format: JPG Size (MB): 1 Pixel Dimensions: 3292 x 1396 Description: The 400-million year old Devonian Chattanooga Shale along Ky. 100 in Monroe County contains enough organic matter to burn. It breaks down quickly when exposed, and may swell when wet and shrink when dry. Photo by Dan Carey, Kentucky Geological Survey.