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Exploring the Geology of the Cincinnati/Northern Kentucky Region” Is the Result Exploring the Geology of the Cincinnati/ Northern Kentucky Region Paul Edwin Potter Second revised edition KENTUCKY GEOLOGICAL SURVEY James C. Cobb, State Geologist and Director UNIVERSITY of KENTUCKY, Lexington SPECIAL PUBLICATION 8 Series XII, 2007 Kentucky Geological Survey James C. Cobb, State Geologist and Director University of Kentucky, Lexington Exploring the Geology of the Cincinnati/ Northern Kentucky Region Paul Edwin Potter Second revised edition Front cover: Downtown Cincinnati, the northern Kentucky city of Ludlow, and the Ohio River, looking east and upstream from the overlook at Mount Echo Park in Price Hill. The topographic basin occupied by Cincinnati’s business district and Covington was formerly a course of the north-flowing Licking River, and the steep hill below the overlook is the result of erosion by the Ohio River as it flows west toward Anderson Ferry. Special Publication 8 Series XII, 2007 Our Mission Our mission is to increase knowledge and understanding of the mineral, energy, and water resources, geologic hazards, and geology of Kentucky for the benefit of the Commonwealth and Nation. © 2006 University of Kentucky Earth Resources—OurFor further information Common contact: Wealth Technology Transfer Officer Kentucky Geological Survey 228 Mining and Mineral Resources Building University of Kentucky Lexington, KY 40506-0107 www.uky.edu/kgs ISSN 0075-5591 Technical Level Technical Level General Intermediate Technical General Intermediate Technical ISSN 0075-5613 Contents Preface ......................................................................................................................................................viii Preface to the Second Edition ................................................................................................................viii Dedication ................................................................................................................................................viii Acknowledgments .................................................................................................................................... ix Funding Acknowledgments .................................................................................................................... ix Thank You ....................................................................................................................................................x Abstract .........................................................................................................................................................1 Introduction .................................................................................................................................................1 References Cited .............................................................................................................................4 Digging Deeper ..............................................................................................................................4 Yesterday’s Pioneers ...................................................................................................................................6 References Cited ................................................................................................................9 Geologic Evolution ...................................................................................................................................10 Continental Position and Overview ..........................................................................................10 References Cited ..............................................................................................................10 Landscape .....................................................................................................................................10 Four Principal Landscape Regions ...............................................................................12 Landscape Evolution ......................................................................................................14 References Cited ..............................................................................................................17 Digging Deeper ...............................................................................................................22 Bedrock ..........................................................................................................................................23 Subsurface Formations ...................................................................................................23 Precambrian .....................................................................................................................24 Paleozoic Era....................................................................................................................28 References Cited ..............................................................................................................34 Digging Deeper ...............................................................................................................36 Outcropping Formations ............................................................................................................37 Distribution and Characteristics ...................................................................................37 Sedimentation, Cycles, and Sequences ........................................................................46 Fossils................................................................................................................................48 References Cited ..............................................................................................................50 Digging Deeper ...............................................................................................................53 Geologic Structure and the Cincinnati Arch ............................................................................54 References Cited ..............................................................................................................55 Glacial Deposits ............................................................................................................................56 Types and Distribution ..................................................................................................56 Dating Local Ice Sheets ..................................................................................................61 References Cited ..............................................................................................................65 Digging Deeper ...............................................................................................................65 Geologic History and Influence of Far-Distant Events ...........................................................67 Precambrian .....................................................................................................................67 Paleozoic Era....................................................................................................................69 Origin of the Cincinnati Arch .......................................................................................70 The Big Gap: Silurian to Late Tertiary Time ...............................................................71 Pleistocene Glaciations ...................................................................................................72 References Cited ..............................................................................................................72 Digging Deeper ...............................................................................................................73 Contents (Continued) Living and Working with Our Inheritance ...........................................................................................74 Surface Processes .........................................................................................................................74 Soils ...................................................................................................................................74 Mass Wasting ..................................................................................................................75 Swelling Soil, Fill, Shale .................................................................................................78 Floodplains ......................................................................................................................78 Urban Sedimentation .....................................................................................................82 References Cited ..............................................................................................................84 Digging Deeper ...............................................................................................................89 Groundwater ................................................................................................................................92 References Cited ..............................................................................................................95 Digging Deeper ...............................................................................................................95 Geologic Hazards .........................................................................................................................96
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