Skip to main content
U.S. flag

An official website of the United States government

The dual‐domain porosity apparatus: Characterizing dual porosity at the sediment/water interface

February 12, 2019

The characterization of pore-space connectivity in porous media at the sediment/water interface is critical to understanding contaminant transport and reactive biogeochemical processes in zones of groundwater and surface-water exchange. Previous in situ studies of dual-domain (i.e.,
mobile/less-mobile porosity) studies have been limited to solute tracer injections at scales of meters to 100s of meters and subsequent numerical model parameterization using fluid concentration histories. Pairing fine-scale (e.g., sub-meter) geoelectrical measurements with fluid tracer data over time alleviates dependence on flowpath-scale experiments, enabling spatially targeted characterization of shallow sediment/water interface media where biogeochemical reactivity is often high. The Dual-Domain Porosity Apparatus is a field-tested device capable of variable rate-controlled downward flow experiments. The Dual-Domain Porosity Apparatus facilitates meter-scale inference of dual-domain parameters, i.e., mobile/less-mobile exchange rate coefficient and the ratio of less mobile to mobile porosity. The Dual-Domain Porosity Apparatus experimental procedure uses water electrical conductivity as a conservative tracer of differential loading and flushing of pore spaces within the region of measurement. Variable injection rates permit the direct quantification of the flow-dependence of dual-domain parameters, which has been theorized for decades but remains challenging to assess using existing experimental methodologies.

Publication Year 2019
Title The dual‐domain porosity apparatus: Characterizing dual porosity at the sediment/water interface
DOI 10.1111/gwat.12846
Authors Courtney R. Scruggs, Martin A. Briggs, Frederick D. Day-Lewis, Dale D. Werkema, John W. Lane
Publication Type Article
Publication Subtype Journal Article
Series Title Groundwater
Index ID 70202178
Record Source USGS Publications Warehouse
USGS Organization WMA - Earth System Processes Division