KENTUCKY GEOLOGICAL SURVEY Donald C. Haney, State Geologist and Director University of Kentucky, Lexington THE EAST CONTINENT RIFT BASIN: A NEW DISCOVERY James A. Drahovzal, David C. Harris, Lawrence H. Wickstrom, Dan Walker, Mark T. Baranoski, Brian Keith, and Lloyd C. Furer Compiled and edited by David C. Harris CINCINNA Tl ARCH CONSORTIUM IND/ANA GEOLOGICAL SURVEY SPECIAL PUBLICATION 18 KENTUCKY GEOLOGICAL SURVEY OHIO DEPARTMENT OF NATURAL RESOURCES SERIES XI, 1992 DIVISION OF GEOLOGICAL SURVEY PUBLISHED ALSO AS: Indiana Geological Survey Special Report 52 Ohio Department of Natural Resources Information Circular 57 Division of Geological Survey Prepared and published by the Kentucky Geological Survey Lexington, Kentucky 1992 ISSN 0075-5613 KENTUCKY GEOLOGICAL SURVEY UNIVERSITY OF KENTUCKY, LEXINGTON Donald C. Haney, State Geologist and Director THE EAST CONTINENT RIFT BASIN: A NEW DISCOVERY James A. Drahovzal David C. Harris Lawrence H. Wickstrom Dan Walker Mark T. Baranoski Brian D. Keith Lloyd C. Furer Compiled and edited by David C. Harris CINCINNATI ARCH CONSORTIUM Indiana Geological Survey Kentucky Geological Survey Ohio Department of Natural Resources, Division of Geological Survey SPECIAL PUBLICATION 18 SERIES XI, 1992 UNIVERSITY OF KENTUCKY Garland R. Dever, Jr., Geologist VII Charles T. Wethington, Jr., President Donald R. Chesnut, Jr., Geologist V Linda J. Magid, Vice President for Research and Cortland F. Eble, Geologist V Graduate Studies David A. Williams, 'Geologist V, Henderson Office Jack Supplee, Director, Fiscal Affairs and Sponsored Warren H. Anderson, Geologist IV Project Administration Gerald A. Weisenfluh, Geologist IV Stephen F. Greb, Geologist Ill KENTUCKY GEOLOGICAL SURVEY ADVISORY Robert Andrews, Geologist I BOARD Breck Cummings, Research Assistant Steve Cawood, Chairman, Pineville Petroleum and Stratigraphy Section: Larry R. Finley, Henderson Hugh B: Gabbard, Richmond James A. Drahovzal, Head Kenneth Gibson, Madisonville Martin C. Noger, Geologist VII Wallace W. Hagan, Lexington Terence Hamilton-Smith, Geologist V Phil M. Miles, Lexington Patrick J. Gooding, Geologist IV W. A. Mossbarger, Lexington David C. Harris, Geologist IV Ralph Palmer, Winchester Brandon C. Nuttall, Geologist IV Henry A. Spalding, Hazard Joseph F. Meglen, Geologist II Ralph N. Thomas, Owensboro James B. Harris, Post-Doctoral Scholar George H. Warren, Jr., Owensboro Dan Walker, Post-Doctoral Scholar David A. Zegeer, Lexington Robert R. Daniel, Laboratory Technician B David E. McFadden, Senior Laboratory Assistant KENTUCKY GEOLOGICAL SURVEY Robyn A. Johnson, Staff Assistant IV Donald C. Haney, State Geologist and Director Anna E. Watson, Staff Assistant IV John D. Kiefer, Assistant State Geologist for Adminis­ Frances A. Benson, Staff Assistant IV tration Luanne Davis, Staff Assistant IV James C. Cobb, Assistant State Geologist for Re- search Theola L. Evans, Staff Assistant IV ADMINISTRATIVE DIVISION Water Resources Section: James S. Dinger, Head Personnel and Finance Section: James A. Kipp, Geologist V James L. Hamilton, Administrative Staff Officer II Daniel I. Carey, Hydrologist IV Roger S. Banks, Account Clerk V James C. Currens, Geologist IV Clerical Section: David R. Wunsch, Geologist IV Marilyn J. Wooten, Staff Assistant VII Alex W. Fogle, Hydrologist Ill Jody L. Fox, Staff Assistant VI Philip G. Conrad, Geologist II Shirley D. Dawson, Staff Assistant V David L. Harmon, Geologist II Eugenia E. Kelley, Staff Assistant V Dwayne M. Keagy, Geologist II Juanita G. Smith, Staff Assistant V, Henderson Office Shelley A. Minns, Research Assistant Publications Section: Ed Fortner, Jr., Geological Technician Donald W. Hutcheson, Head C. Douglas R. Graham, Geological Technician Margaret Luther Smath, Geologic Editor Ill Computer and Laboratory Services Section: Terry D. Hounshell, Chief Cartographic Illustrator Richard A. Smath, Geologist 111 , ESIC Coordinator Steven J. Cordiviola, Head Robert C. Holladay, Principal Drafting Technician Richard E. Sergeant, Geologist V Michael L. Murphy, Drafting Technician Joseph B. Dixon, Systems Programmer William A. Briscoe, 111, Publication Sales Supervisor Henry E. Francis, Associate Scientist Kenneth G. Otis, Stores Worker Zhalet Baharestan, Senior Research Analyst Xenia P. Culbertson, Research Analyst GEOLOGICAL DIVISION Edward H. Heeg, Senior Laboratory Technician Coal and Minerals Section: Steven R. Mock, Senior Laboratory Technician James C. Cobb, Head Mark F. Thompson, Research Analyst CONTENTS Page Abstract ...... .. .... ....... ...... .. .... .... .... ... .. ... ..... ...... ............. 1 Introduction . 2 Previous Work . 2 Regi_onal Precambrian Geology of the Tri-State Area . 2 Gravity Studies .. ............ ........ .. .. ... ... ........ .. ............... .... 3 Magnetic Studies . 3 Basin Models and Hypotheses . 6 Discussion . 6 Stratigraphy of the Middle Run Formation . 6 Regional Distribution of the Middle Run Formation . 6 Depositional Setting and Provenance . 7 Distribution and Geochemistry of Mafic Volcanics . 1 o Age of the East Continent Rift Basin . 1O Basin Boundaries and Structure . 11 Eastern Boundary . 11 Northern Boundary . 11 Southern Boundary . 16 Western Boundary . 16 Precambrian Crystalline Basement Structure . 16 Thickness of the East Continent Rift Basin Fill . 16 Origin of the East Continent Rift Basin . 17 Basalts and Other Igneous Rocks . 17 Sedimentary Fill . 17 Continuity . 17 Block Faulting . 17 Tectonic Relationships . 17 Geologic Evolution of the East Continent Rift Basin . 18 Economic Significance . 20 Conclusions . 20 Acknowledgments . 21 References Cited . 21 TABLE Page 1. List of Wells Penetrating Middle Run Formation, and Associated Mafic and Felsic Volcanics Within the East Continent Rift Basin . 9 ILLUSTRATIONS Figure Page 1. Index map showing relationship of Precambrian tectonic provinces and structural features in the United States Midcontinent to the study area . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 2 2. Regional isostatic residual gravity anomaly map of the east-central United States . 4 3. Regional magnetic anomaly map of the east-central United States . 5 4. Pre-Knox unconformity stratigraphic correlation chart for southeastern Indiana, southwestern Ohio, and central Kentucky . 7 5. Map of the study area showing the location and lithology of Middle Run Formation and re lated intrabasinal volcanic rocks in the East Continent Rift Basin . 8 6. Structure-contour map of the Precambrian crystalline basement surface . 12 7. lsopach map of the East Continent Rift Basin fill . .. .. .. .. .. .. .. .. .. .. .. .. .. 13 8. Regional map showing boundaries of the ECRB and relationship to other Precambrian rifts . 14 9. True-depth interpretation of proprietary seismic line in Jessamine and Madison Counties, Kentucky, showing the eastern boundary of the East Continent Rift Basin . 15 10. Evolution of the East Continent Rift Basin . 19 THE EAST CONTINENT RIFT BASIN: A NEW DISCOVERY James A. Drahovzal1 David C. Harris1 Lawrence H. Wickstrom2 Dan Walker1 Mark T. Baranoski2 Brian D. Keith3 Lloyd C. Furer3 ABSTRACT The presence of a Precambrian sedimentary basin in the eastern Midcontinent, while suspected from geophysical evidence for years, was not proven until the Ohio Geological Survey cored lithic sandstones below.