Back to Search Start Over

Evidence for preferential flow through sandstone aquifers in Southern Wisconsin

Authors :
Kenneth R. Bradbury
Susan K. Swanson
Kristin M. Anderson
Jean M. Bahr
Source :
Sedimentary Geology. 184:331-342
Publication Year :
2006
Publisher :
Elsevier BV, 2006.

Abstract

Sandstones often escape extensive hydrogeologic characterization due to their high primary porosity and perceived homogeneity of permeability. This study provides evidence for laterally extensive, high permeability zones in the Tunnel City Group, an undeformed, Cambrian-aged sandstone unit that exists in the subsurface throughout much of central and southern Wisconsin, USA. Several discrete high-permeability zones were identified in boreholes using flow logging and slug tests, and the interconnectedness of the features was tested using a site-specific numerical model for springs in the region. Explicit incorporation of a high-permeability layer leads to improvements in the flux calibration over simulations that lack the features, thus supporting the hydraulic continuity of high-permeability zones in the sandstone aquifer over tens of kilometers. The results suggest that stratigraphically controlled heterogeneities like contrasts in lithology or bedding-plane fractures, which have been shown to strongly influence the flow of groundwater in more heterogeneous sedimentary rocks, may also deserve close examination in sandstone aquifers.

Details

ISSN :
00370738
Volume :
184
Database :
OpenAIRE
Journal :
Sedimentary Geology
Accession number :
edsair.doi...........95a5b746799c4d44860444a832ef8326
Full Text :
https://doi.org/10.1016/j.sedgeo.2005.11.008