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Upper Jurassic Norphlet, Smackover, and Haynesville deposition in Mississippi, Alabama, and Florida was controlled by the Mississippi Interior Salt Basin (MISB) and the Manila and Conecuh Embayments. Salt movement produced local variations in sediment distribution, and pre-Jurassic paleo-highs modified sedimentation. Norphlet lithofacies include eolian quartzose sandstone, alluvial-fluvial red-bed sandstone, alluvial conglomeratic sandstone, and bay black shale. The eolian lithofacies is best developed in the MISB area. The Conecuh Embayment and northern parts of the MISB and Manila Embayment are characterized by red-bed deposits, whereas the conglomerate lithofacies occurs in the updip parts of the study area. The shale lithofacies is present in the MISB and the Conecuh Embayment are s. In the tristate region, the Smackover Formation consists of a lower intertidal to subtidal, laminated mudstone lithofacies that overlies the Norphlet and an upper subtidal to intertidal lithofacies sequence dominated by grain-supported textures. The upper subtidal oolitic grainstone lithofacies is best developed in the MISB area. The Conecuh Embayment is characterized by subtidal peloidal packstone and intertidal laminated mudstone. Peritidal dolostone is the dominant lithology in the Manila Embayment area. The Buckner Anhydrite Member of the Haynesville Formation usually overlies the Smackover. This evaporite lithofacies is well developed in the southeastern part of the MISB, but thins eastward into the Conecuh Embayment. Upper Haynesville lithofacies change from alluvial-fluvial red bed dominated lithologies in the northern parts of the study area to supratidal-intertidal evaporite, limestone, and shale to the south. Over 100 oil and gas fields have been discovered in the tristate area with Smackover carbonate and Norphlet sandstone the primary reservoirs. Petroleum traps are combination traps involving favorable stratigraphy and salt features. Smackover algal mudstone is probably the source rock for the Jurassic oil.

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