T279 Recent Advances in Using Near-Surface Geophysics to Solve Geological Problems

Wednesday, 7 November 2018
1:30 PM - 5:30 PM
Room 235

ESTIMATION OF HYDRAULIC CONDUCTIVITY USING NEAR-SURFACE GEOPHYSICAL TECHNIQUES

Paper number: T279-2
Program: Technical Sessions
Time: 1:45 PM – 2:00 PM

Authors

Abstract

Near-surface hydraulic conductivity is a critical parameter for environmental investigations, agricultural management, and groundwater remediation. Hydraulic conductivity is a spatially heterogeneous variable that is difficult to measure over large areas using conventional point measurements. Although hydraulic conductivity is often estimated using soil texture, these estimates are frequently inaccurate, and soil textures are also difficult to map accurately. In this research, we explore the potential of ground penetrating radar (GPR) and electromagnetic induction (EM) to map hydraulic conductivity in near-surface soils by comparing changes in soil moisture content with time. Data was acquired in an agricultural field using three GPR frequencies before and after a wetting event, and the data was analyzed to determine the near-surface soil moisture. Data was also acquired using a Geonics EM38 to measure electrical conductivity, which was also related to soil moisture. Differences in the soil moisture estimates from these techniques were used to indicate the hydraulic conductivity distribution across the field. Conventional measurements of hydraulic conductivity were also acquired using a guelph permeameter, and the pattern of hydraulic conductivity interpolated from these measurements were compared to those obtained from geophysical data.

Geological Society of America Abstracts with Programs. Vol. 50, No. 6

doi: 10.1130/abs/2018AM-323633

© Copyright 2018 The Geological Society of America (GSA), all rights reserved. Permission is hereby granted to the author(s) of this abstract to reproduce and distribute it freely, for noncommercial purposes. Permission is hereby granted to any individual scientist to download a single copy of this electronic file and reproduce up to 20 paper copies for noncommercial purposes advancing science and education, including classroom use, providing all reproductions include the complete content shown here, including the author information. All other forms of reproduction and/or transmittal are prohibited without written permission from GSA Copyright Permissions.