Simulation of submarine groundwater discharge salinity and temperature variations: Implications for remote detection

A.M. Dausman; C.D. Langevin; M.C. Sukop

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Simulation of submarine groundwater discharge salinity and temperature variations: Implications for remote detection

A.M. Dausman·C.D. Langevin·M.C. Sukop

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Abstract

A hydrological analysis using a numerical simulation was done to identify the transient response of the salinity and temperature of submarine groundwater discharge (SGD) and utilize the results to guide data collection. Results indicate that the amount of SGD fluctuates depending on the ocean stage and geology, with the greatest amount of SGD delivered at low tide when the aquifer is in direct hydraulic contact with the ocean. The salinity of SGD remains lower than the ocean throughout the year; however, the salinity difference between the aquifer and ocean is inversely proportional to the ocean stage. The temperature difference between the ocean and SGD fluctuates seasonally, with the greatest temperature differences occurring in summer and winter. The outcome of this research reveals that numerical modelling could potentially be used to guide data collection including aerial surveys using electromagnetic (EM) resistivity and thermal imagery.

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A.M. Dausman, C.D. Langevin, M.C. Sukop. 2007. Simulation of submarine groundwater discharge salinity and temperature variations: Implications for remote detection. https://pubs.usgs.gov/publication/70030579

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