Geology of the County
 

In Lee County, water is obtained from consolidated sedimentary rocks ranging in age from Mississippian to Pennsylvanian, and from unconsolidated sediments of Quaternary age. 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 to the northeast and deposited as a great delta. The Mississippian limestone found in Lee County was deposited 350 million years age in the bottom of a warm, shallow sea. At the end of the Mississippian, 320 million years ago, the seas receded and sediments of the Pennsylvanian were deposited. The warm climate of the Pennsylvanian grew extensive forests and great coastal swamps 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 non-vegetative sediments such as sand, clay and silt were compressed into sandstone and shale. Over the last one million years unconsolidated Quaternary sediments have been deposited along the larger streams and rivers.

Geologic Formations in the County
Unconsolidated deposits
ALLUVIUM (Qa)

Limestones
PARAGON FORMATION (Mpn)

Sandstones
GRUNDY FORMATION(contains Lee type sandstone of the former Lee Formation)
(Plc)

Interbedded clay shales, siltstones, and sandstones
BORDEN FORMATION (MDbb)

Coals, sandstones, and shales
BREATHITT GROUP (Pbm, Pbl) (Princess Formation, Four Corners Formation, Hyden
Formation, Pikeville Formation)

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.

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