.....................................................................................................................................9 Acknowledgments ......................................................................................................................9 Introduction....................................................................................................9 Stratigraphy..................................................................................................10 Devonian stable shelf.............................................................................10 The Acadian delta........................................................................... .......12 The regional facies model...................................................................12 The Catskill delta ................................................................................13 Middle Devonian strata..............................................13 Hamilton Group and equivalent strata .......................13 Tully Limestone.........................................................14 Regional unconformity ..............................................14 Upper Devonian and Lower Mississippian strata...................14 Post-unconformity Devonian and Mississippian black gas shales..........................................................14 Brallier Formation and equivalent strata ...................16 Price-Rockwell (Pocono) delta ...........................................................17 Definition and distribution .....................................................17 Price Formation.............................................. ..........17 Virginia and southern West Virginia .........................17 Northern West Virginia, Maryland, and Pennsylvania ..............................................................18 Progradational delta deposits .....................................19 Patton Shale Member.................................................20 Sea level transgression and unconformities ...............20 Burgoon and Purslane Formations.................................21 Maccrady Fomration ..............................................................21 The Berea delta ...................................................................................22 Mississippian stable shelf ............................................................................................22 Upper Mississippian Greenbrier/Newman Limestones ...................................22 Tennessee, southwestern Virginia, eastern Kentucky, and southern West Virginia.....................................................................................23 Northern West Virginia ......................................................................23 Pennsylvania and Maryland................................................................23 Ohio ....................................................................................................24 Regional isopach.................................................................................24 Petroleum geology....................................................................................................................25 General.........................................................................................................................25 The assessment model .....................................................................................25 Thermal maturation data .................................................................................25 Petroleum system events .................................................................................26 Devonian Shale–Middle and Upper Paleozoic total petroleum system.......................27 Part I: Continuous oil and gas resources .........................................................27 Greater Big Sandy Assessment Unit (GBS AU) ................................28 Introduction ............................................................................28 Stratigraphy ............................................................................28