title: Long distance seawater intrusion through a karst conduit network in the Woodville Karst Plain, Florida.
abstract: Five periods of increased electrical conductivity have been found in the karst conduits supplying one of the largest first magnitude springs in Florida with water. Numerous well-developed conduit networks are distributed in the Woodville Karst Plain (WKP), Florida and connected to the Gulf of Mexico. A composite analysis of precipitation and electrical conductivity data provides strong evidence that the increases in conductivity are directly tied to seawater intrusion moving inland and traveling 11 miles against the prevailing regional hydraulic gradient from from Spring Creek Spring Complex (SCSC), a group of submarine springs at the Gulf Coast. A geochemical analysis of samples from the spring vent rules out anthropogenic contamination and upwelling regional recharge from the deep aquifer as sources of the rising conductivity. The interpretation is supported by the conceptual model established by prior researchers working to characterize the study area. This paper documents the first and longest case of seawater intrusion in the WKP, and also indicates significant possibility of seawater contamination through subsurface conduit networks in a coastal karst aquifer.
authors.affiliation: Department of Earth, Ocean and Atmosphere Science, Florida State University, Tallahassee, Florida 32306, USA.|Climate and Ecosystem Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
authors.forename: Zexuan
authors.initials: Z
authors.lastname: Xu
authors.affiliation: Florida Geological Survey, Tallahassee, Florida 32303, USA.
authors.forename: Seth Willis
authors.initials: SW
authors.lastname: Bassett
authors.affiliation: Department of Earth, Ocean and Atmosphere Science, Florida State University, Tallahassee, Florida 32306, USA.|Department of Ecology, Jinan University, Guangzhou, Guangdong, China.
authors.forename: Bill
authors.initials: B
authors.lastname: Hu
authors.affiliation: Florida Geological Survey, Tallahassee, Florida 32303, USA.
authors.forename: Scott Barrett
authors.initials: SB
authors.lastname: Dyer