Analyzing Tidal Fluctuations in the Big Pine Key Freshwater Lens with Time-Lapse Resistivity

Authors

Nicole M. Tucker, Florida International UniversityFollow

Document Type

Thesis

Degree

Master of Science (MS)

Major/Program

Geosciences

First Advisor's Name

Dean Whitman

First Advisor's Committee Title

Committee Chair

Second Advisor's Name

Michael Sukop

Third Advisor's Name

Florentin Maurrasse

Keywords

Geophysics, Hydrogeology, Electrical Resistivity, Freshwater Lens, Big Pine Key, Tidal Monitoring, Groundwater Model, Miami Oolite, Key Largo Limestone

Date of Defense

5-20-2013

Abstract

The tidal influence on the Big Pine Key saltwater/freshwater interface was analyzed using time-lapse electrical resistivity imaging and shallow well measurements. The transition zone at the saltwater/freshwater interface was measured over part of a tidal cycle along three profiles. The resistivity was converted to salinity by deriving a formation factor for the Miami Oolite. A SEAWAT model was created to attempt to recreate the field measurements and test previously established hydrogeologic parameters. The results imply that the tide only affects the groundwater within 20 to 30 m of the coast. The effect is small and caused by flooding from the high tide. The low relief of the island means this effect is very sensitive to small changes in the magnitude. The SEAWAT model proved to be insufficient in modeling this effect. The study suggests that the extent of flooding is the largest influence on the salinity of the groundwater.

Identifier

FI13080512

Recommended Citation

Tucker, Nicole M., "Analyzing Tidal Fluctuations in the Big Pine Key Freshwater Lens with Time-Lapse Resistivity" (2013). FIU Electronic Theses and Dissertations. 947.
https://digitalcommons.fiu.edu/etd/947