Patterns of groundwater salinity changes in a deep continental-oceanic transect off the southeastern Atlantic coast of the U.S.A.

F.T. Manheim; C. K. Paull

doi:10.1016/0022-1694(81)90154-2

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Patterns of groundwater salinity changes in a deep continental-oceanic transect off the southeastern Atlantic coast of the U.S.A.

F.T. Manheim·C. K. Paull

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Abstract

Investigations of formation-fluid salinities in a transect from western Georgia to the edge of the Blake Plateau off the coast of Georgia show surprisingly similar hydrochemical features offshore and onshore. A fresh-brackish wedge of groundwater (<25 g/kg total dissolved solids) lies beneath the shelf to a depth of ∼ 900 m. On land, brackish waters extend to a maximum depth of ∼ 1.2 km below sea level in Lowndes County, Georgia. In deeper horizons, hypersaline brines (> 100 g/kg) occur in Lower Cretaceous (?) strata. These strata have a pronounced evaporitic (anhydritic) character in the offshore segment. Strong salinity gradients in interstitial waters signify buried evaporite deposits at drill sites beneath the Blake Plateau.

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Journal of Hydrology Article

Source-reported bounding extent: 29.204934495587977° to 33.8070332900253° latitude; -81.47050643744609° to -78.96091688004468° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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F.T. Manheim, C. K. Paull. 1981. Patterns of groundwater salinity changes in a deep continental-oceanic transect off the southeastern Atlantic coast of the U.S.A.. https://doi.org/10.1016/0022-1694(81)90154-2

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