Regional Norphlet facies correlation, analysis and implications for paleostructure and provenance, eastern Gulf of Mexico
Norphlet Formation paleotransport is controlled by wind and structure. Facies analysis of the Norphlet Formation shows that structurally routed wadis and alluvial fans are the primary methods for introducing sediment into the Norphlet system. Structural highs provided sediment sources and grabens and basins focused the wadi systems into distinct Norphlet sediment transport systems. Eolian transport directions, calculated from dipmeter analyses, are consistent with the transit directions necessary to redistribute wadi derived sediment into the patterns previously determined from zircon analysis; the primary directions of Norphlet transport are southward from the Appalachian Mountains and westward/northwestward from Florida. Haynesville zircon detrital analysis implies that the sediment transport paths were persistent through Late Jurassic time. Interpretations of regional 2D prestack depth migrated seismic shows that the Norphlet reflector is persistent through the Eastern Gulf of Mexico. The Middle Ground Arch paleohigh shows erosion during the time of Norphlet deposition and was likely a sediment source for the Norphlet Formation. Integration of the seismic data with the transport model indicates the Norphlet should be present in the Tampa Embayment as well as areas adjacent to the Middle Ground Arch. The eolian facies is extensive with erg migration to the north or northeast in the present offshore and migration generally to the south in onshore Alabama and Florida. The down dip limit of the Norphlet was likely controlled by sediment availability and there may not be a regional, standing water, downdip Norphlet facies.