HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Figures Only Full Text Free Full Text (PDF) Free Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in ISI Web of Science Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (1) Citing Articles via Google Scholar Google Scholar Articles by Hall, L. M. Articles by Hendrickx, J. M. H. Search for Related Content PubMed Articles by Hall, L. M. Articles by Hendrickx, J. M. H. GeoRef GeoRef Citation Agricola Articles by Hall, L. M. Articles by Hendrickx, J. M. H. Related Collections Vadose Zone Processes and Chemical Transport Field-Scale Studies Electromagnetic Induction, EMI

SPECIAL SECTION: HYDROGEOPHYSICS

Determination of Solute Distributions in the Vadose Zone Using Downhole Electromagnetic Induction

^a New Mexico Institute of Mining and Technology, Department of Earth and Environmental Science, 801 Leroy Place, Socorro, NM 87801
^b Sandia National Laboratories, Geohydrology Department, P.O. Box 1101, Sandia Park, NM 87047
^* Corresponding author (bowman{at}nmt.edu). Published in Vadose Zone Journal 3:1207–1214 (2004)

Received 29 January 2004.

We conducted a field experiment to evaluate the ability of downhole electromagnetic induction (EM) measurements to track the migration of a salt plume in the vadose zone. A 6.9 g L^–1 slug of NaCl was applied to a 3 by 3 m area for 85 d at a flux of 2.7 cm d^–1. Electrical conductivity measurements were collected weekly, using 13 12-m boreholes installed in a 15 by 15 m area. The measured bulk soil electrical conductivity (EC_a) was converted to soil water electrical conductivity (EC_w) using water contents from neutron probe measurements and clay contents from soil cores. The calculated mass of salt in the profile agreed well with the known mass of salt infiltrated when the appropriate immobile water content was assumed. The low water content, _w, (<15% by volume) and low bulk soil electrical conductivity, EC_a, (<100 mS m^–1) measured at the test site presented more resistive conditions than previous studies of this type and were a cause of uncertainty in the results. Good agreement between calculated and known EC_w resulted from the ability to measure _w and EC_a in the same locations. Sensitivity analyses showed that the calculated EC_w was strongly dependent on the assumed upper limit of immobile water content, and less sensitive to soil temperature and clay content. The results of this study demonstrate that downhole EM methods can accurately characterize water and solute distributions in the vadose zone.

Abbreviations: EM, electromagnetic induction

This article has been cited by other articles:

				H. Vereecken, S. Hubbard, A. Binley, and T. Ferre Hydrogeophysics: An Introduction from the Guest Editors Vadose Zone J., November 1, 2004; 3(4): 1060 - 1062. [Full Text] [PDF]