CCU groundwater and resistivity study - Winter 2013 Dr. Richard N. Peterson Coastal Carolina University

Center for Marine and Wetland Studies 1270 Atlantic Avenue, Room 111 Coastal Carolina University Conway South Carolina 29526 USA

rpeters2@coastal.edu Georgia Coastal Ecosystems LTER Project

Dept. of Marine Sciences University of Georgia Athens Georgia 30602-3636 USA

gcelter@uga.edu https://gce-lter.marsci.uga.edu/ Dr. Richard N. Peterson Coastal Carolina University

Center for Marine and Wetland Studies 1270 Atlantic Avenue, Room 111 Coastal Carolina University Conway South Carolina 29526 USA

rpeters2@coastal.edu Principal investigator Matthew Carter Coastal Carolina University

Center for Marine and Wetland Studies 1270 Atlantic Avenue Coastal Carolina University Conway South Carolina 29526 USA

mlcarte2@g.coastal.edu Co-investigator Dr. Richard F. Viso Coastal Carolina University

Center for Marine and Wetland Studies 1270 Atlantic Avenue Coastal Carolina University Conway South Carolina 29526 USA

rviso@coastal.edu http://ww2.coastal.edu/rviso/ Co-investigator 2026

Our goal during this research effort will include: 1.) Collect shallow marsh sediment cores with the use of a vibracore sampling system 2.) Electrical resistivity measurements. Vibracore sampling: A shore normal transect of cores will be taken at 3 sites to characterize the shallow marsh sediment. The sediment cores will be taken back to Coastal Carolina for further analyses that include grain-size analysis, radon sediment equilibration, and bench-top sediment salinity resistivity calibration. Geophysical measurements: subsurface resistivity time-series measurements will be conducted by laying a resistivity cable (100m) along a transect form the upland through the marsh and into the river. The cable will remain on the ground surface for about 24hrs measuring the subsurface resistivity. In addition to the resistivity measurements, we will collect 6-L groundwater grab samples from existing piezometers located at Moses Hammock. This effort will use a self-contained peristaltic pump and tubing to collet water into our gas tight radon analysis bottles.

Area 2: Patterns within the Domain (more information)

marsh salinity sedimentology LTER NSF GCE geology geophysics Overall geographic extent of the research project -81.295500 -81.277455 31.459769 31.416170 2013-12-03 2013-12-06

GCE-LTER sub-award for groundwater quantification, NSF, $75K

estuary marsh complex LumberLanding - Lumber Landing dock on the Duplin River at Sapelo Island, Georgia -81.277455 -81.277455 31.459769 31.459769 Marsh_Landing_ML - Marsh_Landing_ML sampling site used by Amy Kunza in 2005 to study plant species richness -81.295500 -81.295500 31.416170 31.416170 Map (Google Earth KML/KMZ or map image) https://gce-lter.marsci.uga.edu/private/registration/files/Maps/GCE-53-2013_Maps_Duplin_River_Field_Survey_December_2013.kmz

Ferry landing sediment cores: 31°25'5.18"N 81°17'43.15"W 31°25'3.78"N 81°17'39.10"W 31°25'1.51"N 81°17'36.44"W Lumber landing sediment cores: 31°27'29.12"N 81°16'41.75"W 31°27'29.04"N 81°16'41.08"W Moses Hammock sediment cores: 31°28'39.53"N 81°16'21.13"W 31°28'39.70"N 81°16'20.83"W Electrical Resistivity Transect in line with the Moses Hammock sediment core GPS.

A 100 meter electrode array and control box will be deployed in a short 24 hour period. After the survey is conducted the electrode array will be removed. The vibracore system consists of an 8ft. aluminum tripod, a small portable generator, a vibracore head, and 7 (2.5 meter) aluminum core pipes. This deployment will be broken down daily.

Peterson, R.N., Meile, C., Peterson, L., Carter, M. and Miklesh, D.M. 2019. Groundwater discharge dynamics into a salt marsh tidal river. Estuarine, Coastal and Shelf Science. 218:324-333. (DOI: 10.1016/j.ecss.2019.01.007) Peterson, R.N., Meile, C., Carter, M., Peterson, L., Waldorf, A. and Miklesh, D.M. 2017. Poster: Groundwater inputs to a back-barrier salt marsh tidal river. 2017 Chemical Oceanography Gordon Research Conference, July 2017, Holderness, NH.