|Geology of the County
In Wayne County, water is obtained from consolidated sedimentary rocks of Mississippian and Pennsylvanian age, and from unconsolidated sediments of Quaternary age. Geologists call the oldest rocks found at the surface in Wayne County the Fort Payne Formation. This Mississippian formation was deposited in warm seas 350 million years ago. The Mississippian sandstones and siltstones are the result of a great influx of mud, silts, and sands brought in by rivers and streams from uplands many miles away and deposited as a great delta. At the end of the Mississippian, 320 million years ago, the seas receded and sediments of the Pennsylvanian Period were deposited. The warm climate of the Pennsylvanian allowed extensive forests to grow and great coastal swamps to form at the edges of water bodies. Marine waters advanced and receded many times, which produced many layers of sandstone, shale, and coal. Vegetation of all sorts fell into the water and was buried under blankets of sediments, which over long geologic time were compressed into coal. The nonvegetative sediments such as sand, clay, and silt were compressed into sandstone and shale. Over the last million years, unconsolidated Quaternary sediments have been deposited along the larger streams and rivers.
Geologic Formations in the County
Coals, sandstones, and shales
For more information, see the definitions of geologic terms and rock descriptions, a geologic map of the county, a summary of the geology of Kentucky, and a discussion of fossils and prehistoric life in Kentucky.