Subsurface Facies Analysis of the Devonian Berea Sandstone in Southeastern Ohio
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SUBSURFACE FACIES ANALYSIS OF THE DEVONIAN BEREA SANDSTONE IN SOUTHEASTERN OHIO William T. Garnes A Thesis Submitted to the Graduate College of Bowling Green State University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE December 2014 Committee: James Evans, Advisor Jeffrey Snyder Charles Onasch ii ABSTRACT James Evans, Advisor The Devonian Berea Sandstone is an internally complex, heterogeneous unit that appears prominently both in outcrop and subsurface in Ohio. While the unit is clearly deltaic in outcrops in northeastern Ohio, its depositional setting is more problematic in southeastern Ohio where it is only found in the subsurface. The goal of this project was to search for evidence of a barrier island/inlet channel depositional environment for the Berea Sandstone to assess whether the Berea Sandstone was deposited under conditions in southeastern Ohio unique from northeastern Ohio. This project involved looking at cores from 5 wells: 3426 (Athens Co.), 3425 (Meigs Co.), 3253 (Athens Co.), 3252 (Athens Co.), and 3251 (Athens Co.) In cores, the Berea Sandstone ranges from 2 to 10 m (8-32 ft) thick, with an average thickness of 6.3 m (20.7 ft). Core descriptions involved hand specimens, thin section descriptions, and core photography. In addition to these 5 wells, the gamma ray logs from 13 wells were used to interpret the architecture and lithologies of the Berea Sandstone in Athens Co. and Meigs Co. as well as surrounding Vinton, Washington, and Morgan counties. Analysis from this study shows evidence of deltaic lobe progradation, abandonment, and re-working. Evidence of interdistributary bays with shallow sub-tidal environments, as well as large sand bodies, is also present. A prominent sequence of climbing ripples ≤ 6 cm give evidence for distributary mouth bars. Frequently appearing massive bedding, sparse bioturbation, and a sequence of massive bedding to planar lamination overlying convoluted bedding provides evidence that high sedimentation rates were common during the deposition of the Berea Sandstone. Turbulent debris flows are interpreted based on the presence of a 10 cm iii incomplete turbidite lithofacies assemblage. Tidal processes can be inferred from tidal rhythmite sequences approximately 5 m thick, and clear storm activity is apparent from the presence of a 16 cm tempestite lithofacies assemblage. Geophysical log analysis allowed for the interpretation of the subsurface architecture of the formation. Combined, these features provide strong evidence for the interpretation that, in southeastern Ohio, the Berea Sandstone was deposited in a tidally-influenced, deltaic environment. iv ACKNOWLEDGMENTS I would first like to thank the Graduate College, and entire Geology Department of Bowling Green State University. I am greatly indebted to Dr. James E. Evans for his candid honesty, advice, and constant support throughout my time at Bowling Green State University. I would also like to express my gratitude to the Ohio Geological Survey, specifically Mr. Greg Schumacher, Mr. Aaron Evelsizor, Ms. Madge Fitak, and Mr. Mark Baranoski for the help with collecting core and geophysical log data. I’m obliged to thank Mr. Michael J. Carroll and the National Association of Black Geoscientists for giving me an opportunity to present my thesis proposal, and reinvigorating my passion for the geosciences. To my Alpha Phi Alpha fraternity brothers Jeremy Stewart, Titus Austin, Malcom McIver, Bernard White, and my best friend Aaron Ruth I am indebted for their constant financial, spiritual, and emotional support. Of course I must graciously thank my parents Harold and Sharon Garnes for their constant love and encouragement. I’m grateful to my brothers Harold and Randolph for providing me with a car, my cousin Frank Sawyer for always being there to help, my girlfriend Ashley for all her love and support, and my uncles Thomas Sawyer and Craig Sawyer and aunts Neida Sawyer and Allison Currie for taking such an interest in my future. v TABLE OF CONTENTS Page INTRODUCTION ........................................................................................................................ 1 Deltaic Environments........................................................................................................ 1 Subaerial Delta Plains ........................................................................................... 1 Interdistributary Bays............................................................................................ 2 Delta Front ............................................................................................................ 5 Prodelta ................................................................................................................. 6 Barrier Island Complexes ................................................................................................. 7 Beach Zonation ..................................................................................................... 9 Barrier Islands ..................................................................................................... 11 Estuaries .............................................................................................................. 14 Lagoons ............................................................................................................... 15 Tidal Inlets .......................................................................................................... 17 Purpose and Goals........................................................................................................... 18 GEOLOGIC BACKGROUND ................................................................................................... 20 Regional Geologic Setting .............................................................................................. 20 vi Regional Stratigraphy ..................................................................................................... 20 Pre-Cambrian ...................................................................................................... 20 Cambrian ............................................................................................................. 22 Ordovician........................................................................................................... 22 Silurian ................................................................................................................ 23 Devonian ............................................................................................................ 23 Berea Sandstone .............................................................................................................. 24 Lithology ............................................................................................................. 27 Stratigraphy & Age ............................................................................................. 28 Geologic History ................................................................................................. 30 Economic Geology.............................................................................................. 31 METHODS ................................................................................................................................. 34 Drill Core ........................................................................................................................ 34 Core Analysis ...................................................................................................... 34 Geophysical Log Analysis .............................................................................................. 35 Gamma-ray logs .................................................................................................. 37 Structure Contour Maps ...................................................................................... 37 vii Isopach Maps ...................................................................................................... 38 Outcrop Analysis ............................................................................................................ 38 RESULTS ................................................................................................................................... 42 Core Descriptions............................................................................................................ 42 Core 3426 ............................................................................................................ 42 Core 3425 ............................................................................................................ 44 Core 3253 ............................................................................................................ 46 Core 3252 ............................................................................................................ 46 Core 3251 ............................................................................................................ 49 Lithology and Thin Section Analysis ............................................................................. 51 Sandstone ............................................................................................................ 51 Siltstone............................................................................................................... 53 Mudstone............................................................................................................