Foreword

Introduction

Acknowledgments

Overview

Water Use

Topography of the County

Geology of the County

Groundwater Availability

Exploration for Groundwater

Karst

Water Quality

Maps and Data

Additional Reading

References Cited

Definitions of Geologic Terms

Rock Descriptions

In Caldwell County, water is obtained from consolidated sedimentary rocks of Mississippian through Pennsylvanian ages and from unconsolidated sediments of the Cretaceous and Quaternary ages. Geologists call the oldest rocks found at the surface in Caldwell County the St. Louis Limestone. The most common rock types in Caldwell County are Mississippian limestones, which were 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 nonvegetative sediments such as sand, clay, and silt were compressed into sandstone and shale. During the latter part of the Cretaceous, 130 million years ago, the Gulf of Mexico inundated much of the southern United States and covered all the
Jackson Purchase and some of the Mississippian Plateaus with sands, clays, and gravels. There geological deposits are a marked contrast to the underlying, older hard rocks, because most of the Cretaceous and younger sediments remain unconsolidated and soft. Over the last one million years Quaternary sediments have been deposited along the larger streams and rivers.

Geologic Formations in the County
Unconsolidated deposits
ALLUVIUM (Qa)
TUSCALOOSA FORMATION (Kt)

Limestones
STE. GENEVIEVE LIMESTONE (Mgl)
ST. LOUIS LIMESTONE (Mgl)

Sandstones
CASEYVILLE FORMATION (Pca)

Coals, sandstones, and shales
TRADEWATER FORMATION (Pt)

Interbedded limestones, sandstones, and shales
KINKAID Limestone, DEGONIA Sandstone, CLORE Limestone (Mcu)
PALESTINE SANDSTONE (Mcu)
MENARD Limestone, WALTERSBURG Sandstone, VIENNA Limestone (Mcu)
TAR SPRINGS SANDSTONE (Mcu)
GLEN DEAN LIMESTONE (Mcl)
HARDINSBURG SANDSTONE (Mcl)
GOLCONDA FORMATION(Haney Limestone, Big Clifty Sandstone, Beech Creek Limestone Members) (Mcl)
PAINT CREEK SHALE (Mcl)
BETHEL SANDSTONE (Mcl)
RENAULT LIMESTONE (Mcl)

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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