Electrical resistivity imaging of the architecture of substream sediments
Article first published online: 9 DEC 2008
Copyright 2008 by the American Geophysical Union.
Water Resources Research
Volume 44, Issue 4, April 2008
How to Cite
2008), Electrical resistivity imaging of the architecture of substream sediments, Water Resour. Res., 44, W00D13, doi:10.1029/2008WR006968., , , , , and (
- Issue published online: 9 DEC 2008
- Article first published online: 9 DEC 2008
- Manuscript Accepted: 3 SEP 2008
- Manuscript Revised: 12 AUG 2008
- Manuscript Received: 1 MAR 2008
 The modeling of fluvial systems is constrained by a lack of spatial information about the continuity and structure of streambed sediments. There are few methods for noninvasive characterization of streambeds. Invasive methods using wells and cores fail to provide detailed spatial information on the prevailing architecture and its continuity. Geophysical techniques play a pivotal role in providing spatial information on subsurface properties and processes across many other environments, and we have applied the use of one of those techniques to streambeds. We demonstrate, through two examples, how electrical resistivity imaging can be utilized for characterization of subchannel architecture. In the first example, electrodes installed in riparian boreholes and on the streambed are used for imaging, under the river bed, the thickness and continuity of a highly permeable alluvial gravel layer overlying chalk. In the second example, electrical resistivity images, determined from data collected using electrodes installed on the river bed, provide a constrained estimate of the sediment volume behind a log jam, vital to modeling biogeochemical exchange, which had eluded measurement using conventional drilling methods owing to the boulder content of the stream. The two examples show that noninvasive electrical resistivity imaging is possible in complex stream environments and provides valuable information about the subsurface architecture beneath the stream channels.