Abstract

The extent of the hyporheic zone is governed by complex physical processes and material properties that are difficult to characterize with well data or in-stream data alone. Here, we explore use of three dimensional electrical resistivity imaging (ERI) to provide spatially distributed information of stream solute transport and image the dominant pathways of solute movement into the hyporheic zone in a synthetic study. A fully coupled three-dimensional finiteelement model of the surface and subsurface system is developed in COMSOL to explore the extent of the hyporheic zone given variations in a series of properties: (1) stream discharge, (2) changes in the hydraulic gradient between aquifer and stream and (3) the width of the stream. We also explore ERI’s ability to image the hyporheic extent under these controls given differences in injected tracer concentration. ERI is found to be well correlated with solute transport data, and both data accurately predict the mean arrival time of stream water within the hyporheic zone and the solute extent into the subsurface.

Citation

Chattopadhyay, P. B., Singha, K., Gooseff, M.N. (2012): Exploring controls on saline tracer movement within the hyporheic zone using finite-element modeling and electrical resistivity. AGU Annual Fall Conference Proceedings.

This Paper/Book acknowledges NSF CZO grant support.