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 Bourbon County, water is obtained from consolidated sedimentary rocks ranging in age from Ordovician to Mississippian, and from unconsolidated sediments of Quaternary age. The oldest rocks exposed on the surface in Kentucky, deposited in shallow seas 450 million years ago during the Early Ordovician Period, are also found in Boyle County. Lying on top of the Ordovician rocks are rocks, including the New Albany Shale, of Devonian age. The New Albany Shale, 400 million years old, is also called the black shale. It was formed when the deep sea floor became covered with an organic black muck. The muck is now hard black shale (an oil shale), which is one of the most distinctive of all geologic formations in Kentucky. 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. The Mississippian limestone found in Boyle County was deposited 350 million years ago in the bottom of a warm, shallow sea. Over the last million years, unconsolidated Quaternary sediments have been deposited along the larger streams and rivers.

Geologic Formations in the County

Limestones
Salem and Warsaw Formations (Msh)
Borden Formation (Mbf)
UPPER PART OF Lexington Limestone (Tanglewood Limestone, Millersburg, Strodes Creek, Devils Hollow, Sulfur Well, Brannon, and Perryville Members) (Ol)
LOWER PART OF Lexington Limestone (Grier, Logana, and Curdsville Members) (Ol)
HIGH BRIDGE GROUP (Tyrone Limestone, Oregon Formation, Camp Nelson Limestone ) (Ohb)

Dolomitic limestone
KNOX GROUP (Okx)

Interbedded clay shales, siltstones, and sandstones
Borden Formation (MDbb)
Garrard Siltstone (Okc)

Fractured shales
New Albany Shale (MDnb)

Interbedded limestones and shales
Drakes Formation (Saluda Dolomite, Bardstown, Rowland Members) (Odc)
ASHLOCK FORMATION, GRANT LAKE LIMESTONE, Calloway Creek Limestone (Oaf)
Clays Ferry Formation (Okc)

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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