Geological Basin’s & Plays
Appalachian Basin
The Appalachian Basin is a foreland basin containing Paleozoic sedimentary rocks of Early Cambrian through Early Permian age. From north to south, the Appalachian Basin Province crosses New York, Pennsylvania, eastern Ohio, West Virginia, western Maryland, eastern Kentucky, western Virginia, eastern Tennessee, northwestern Georgia, and northeastern Alabama. The Appalachian Basin has had a long history of oil and gas production, and much of it has not been systematically recorded; thus, there are no commercial data bases for field size and production history. An ad hoc field file consisting of about 1,100 fields was used in this assessment. It was compiled from published production records from the States of Pennsylvania, West Virginia, New York, and Tennessee which have been kept from the early 1960's; proprietary oil and gas, Energy Information Administration (EIA), U.S. Department of Energy Integrated Field File (OGIFF); published scientific articles and reports; and unpublished industry reports and records.
Cambrian and Lower Ordovician Carbonate Play
The Cambrian and Lower Ordovician Carbonate Play is defined by oil and associated gas trapped in vuggy platform dolomite of Cambrian and Early Ordovician age by truncation traps beneath the widespread Knox unconformity and by small anticlines controlled by basement fault blocks. Stratigraphically, the play involves the Upper Cambrian Copper Ridge Dolomite of the Knox Group, Lower Ordovician Mascot Dolomite of the Knox Group, and Upper Cambrian and Lower Ordovician Knox Dolomite. The play is confirmed and extends across the entire Cincinnati Arch Province. The dolomite reservoirs in the play are classified as conventional
Middle and upper Ordovician carbonate
The Middle and Upper Ordovician Carbonate Play is defined by oil and associated gas trapped in vuggy platform dolomite and bioclastic limestone by facies-change stratigraphic traps, dolomitized fracture zones, and small anticlines controlled by basement faults. Stratigraphically, the play involves the Middle and (or) Upper Ordovician Trenton Limestone, Black River Limestone, High Bridge Group, Lexington Limestone, Stones River Group, and Nashville Group. The play is confirmed and extends across the entire Cincinnati Arch except along crests of the Jessamine (Lexington) and Nashville Domes where the Middle and Upper Ordovician sequence has been eroded. Most limestone and dolomite reservoirs in the play are classified as conventional.
Cincinnati Arch complex
The Cincinnati Arch Province consists of broad, basement-involved arches, domes, and intervening sags and saddles that separate the Appalachian and Illinois Basins. A veneer of Paleozoic sedimentary rocks, as much as 5,000 ft thick, covers the basement rocks. From north to south, the Cincinnati Arch Province includes western Ohio, north-central Indiana, central Kentucky, central Tennessee, and northernmost Alabama
Trenton Black River Carbonate play
The Trenton/Black River Carbonate Oil/Gas Play is defined by oil and gas trapped in Middle Ordovician platform limestone reservoirs by facies-change stratigraphic traps, low-amplitude basement-controlled anticlines, dolomitized fracture zones, and natural fractures. The play involves Middle Ordovician limestone approximately between the Allegheny structural front and the western limit of the Appalachian basin. This play area is northwest of the Valley and Ridge part of the Appalachian Fold and Thrust Belt and contains few, if any, bedding-plane detachment structures in pre-Upper Ordovician rocks. Stratigraphically, the play involves the Middle Ordovician Trenton Group (Limestone), Black River Group (Limestone), Lexington Limestone (in part Upper Ordovician), High Bridge Group, Stones River Group, Nashville Group (in part Upper Ordovician), and Chickamauga Group (Limestone). Also included in the eastern Kentucky part of the play is quartzose sandstone of the St. Peter Sandstone that rests directly on the Knox unconformity.
The play is confirmed and extends across parts of New York, Pennsylvania, Ohio, West Virginia, Kentucky, Virginia, Tennessee, and Alabama. Most prospective reservoirs in the play are conventional.
Mississippian Carbonate Play
The Mississippian Carbonate Play is defined by oil and gas trapped in Mississippian bioherms and platform limestone by facies-change and local combination traps. Stratigraphically, the play involves the Lower Mississippian Fort Payne Formation and the Upper Mississippian Warsaw, St. Louis, Salem, and Monteagle Limestones. The play is confirmed and is mainly in the Cumberland Saddle and adjoining flanks of the Jessamine (Lexington) and Nashville Domes. The limestone reservoirs in the play are classified as conventional.
Rome Trough Play
The Rome Trough is a narrow northeast-trending rift basin that underlies the Appalachian Basin in Pennsylvania, West Virginia, and Kentucky. Approximately 6,000 – 9,000 ft of Lower and Middle Cambrian shallow-marine to peritidal carbonate, sandstone, and shale fill the rift. The Rome Trough Play is defined by gas trapped in sandstone and carbonate reservoirs within the rift by basement-controlled fault blocks and anticlines. Stratigraphically, the play involves the Lower and Middle Cambrian Rome Formation and the Middle and Upper Cambrian Conasauga Group. The play is hypothetical and is confined mostly to the Kentucky and West Virginia part of the Rome Trough. The sandstone and carbonate reservoirs are classified as conventional.
Silurian and Devonian Carbonate play
The Silurian and Devonian Carbonate Play is defined by oil and gas trapped in Silurian and Devonian platform carbonates by truncation, facies change, and combination traps. Stratigraphically, the play involves the Upper Silurian Louisville Limestone, Upper Silurian Laurel Dolomite, Middle Devonian Jeffersonville Limestone, and Middle Devonian Boyle Dolomite. Thin sandstone units such as the Upper Devonian Hardin Sandstone and Knob Lick sandstone are included in the play. The driller's term "Corniferous" limestone or interval is commonly applied to one or all of the previously named units. The play is confirmed and extends across the Cumberland Saddle and adjoining flanks of the Jessamine (Lexington) and Nashville Domes. The limestone, dolomite, and minor sandstone reservoirs in the play are classified as conventional.