Combined use of frequency‐domain electromagnetic and electrical resistivity surveys to delineate the freshwater/saltwater interface near saline lakes in the Nebraska Sand Hills, Nebraska, USA

Proceedings of SAGEEP (Symposium on the Application of Geophysics to Engineering and Environmental Problems)
USGS Ground-Water Resources Program;USGS Toxic Substances Hydrology Program;NSF (non-USGS authors)
By: , and 
Edited by: Dwain K. Butler

Links

Abstract

We investigate the use of frequency‐domain electromagnetic (FDEM) and electrical resistivity (ER) surveys for rapid and detailed characterization of the direction of lake‐aquifer fluxes and the configuration of salt plumes generated from saline lakes. This methodology was developed and applied at several lakes in the Nebraska Sand Hills, Nebraska, in an area with both freshwater and saline lakes hydraulically connected to the freshwater surficial aquifer. The FDEM survey was conducted by mounting the instrument on a fiberglass cart towed by an all‐terrain vehicle. The towed FDEM surveys covered about 25 km per day and served as a reconnaissance method for choosing locations for the more quantitative and detailed ER surveys. Around the saline lakes, areas with high electrical conductivity are consistent with the regional direction of ground‐water flow. Lower electrical conductivity was measured around the freshwater lakes with anomalies correlating to a paleovalley axis inferred from previous studies. The efficacy of this geophysical approach is attributed to: (1) significant contrast in electrical conductivity between freshwater and saltwater, (2) near‐surface location of the freshwater/saltwater interface, (3) minimal cultural interference, and (4) relative homogeneity of the aquifer materials.

Additional publication details

Publication type Conference Paper
Publication Subtype Conference Paper
Title Combined use of frequency‐domain electromagnetic and electrical resistivity surveys to delineate the freshwater/saltwater interface near saline lakes in the Nebraska Sand Hills, Nebraska, USA
Series title Proceedings of SAGEEP (Symposium on the Application of Geophysics to Engineering and Environmental Problems)
ISBN 9781615670512
DOI 10.4133/1.3176693
Year Published 2009
Language English
Publisher Environment and Engineering Geophysical Society
Contributing office(s) OGW Branch of Geophysics
Description 10 p.
Larger Work Type Book
Larger Work Subtype Conference publication
Larger Work Title Proceedinga of the Symposium on the Application of Geophysics to Engineering and Environmental Problems 2009
First page 178
Last page 187
Conference Title Symposium on the Application of Geophysics to Engineering and Environmental Problems 2009
Conference Location Fort Worth, TX
Conference Date March 29 - April 2, 2009
Country United States
State Nebraska
Other Geospatial Nebraska Sand Hills