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Channel sandstones are deposited in fluvial channels, fluvial-dominated deltas, submarine channels, and channel-dominated submarine fans on shelves and slopes of many basins. Excellent models of these channel-sandstone depositional environments and reservoirs are in Upper Pennsylvanian and Lower Permian sediments on the eastern shelves and slopes of the Permian basin. In dip-trending fluvial systems on superimposed coastal plains, sandstone reservoirs are in single and multiple strike-oriented point bars in meander belts, and longitudinal and transverse bars in braided belts. By differential compaction, these sandstone belts may produce oil where they drape over buried paleotopographic features such as reefs, structures, and sandstone bodies. Conversely, reservoirs may be found in and above these buried features by recognizing diversions in the trend of overlying channel-sandstone belts. Oil and gas in sediments adjacent to channels may be trapped by nonpermeable channel-fill barriers. Seismic cross sections of meander belts can clearly show convex-downward bases.
Stratigraphic traps are in thin distributary-channel sandstone facies of shelf-elongate deltas overlying limestone and shale beds and shelf. Shelf-margin lobate deltas have reservoirs in thick delta-front sheet, distributary-channel, and upper delta-plain sandstone facies on top of clastic wedges of sediments on slope.
"Packages" of fine-grained, lenticular turbidites can be correlated in submarine channels and fans on slope. Levees probably border submarine channels. Most Upper Pennsylvanian-Lower Permian slope sandstone reservoirs have been stratigraphically miscorrelated with Lower Pennsylvanian sandstone formations on shelf.
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