A tracer methodology for identifying ambient flows in boreholes
Maurice, L.; Barker, J.A.; Atkinson, T.C.; Williams, A.T.; Smart, P.L.. 2011 A tracer methodology for identifying ambient flows in boreholes. Ground Water, 49 (2). 227-238. 10.1111/j.1745-6584.2010.00708.xBefore downloading, please read NORA policies.
Maurice et al.pdf
Download (1MB) | Preview
Identifying flows into, out of, and across boreholes is important for characterizing aquifers, determining the depth at which water enters boreholes, and determining the locations and rates of outflow. This study demonstrates how Single Borehole Dilution Tests (SBDTs) carried out under natural head conditions provide a simple and cheap method of identifying vertical flow within boreholes and determining the location of in-flowing, out-flowing, and cross-flowing fractures. Computer simulations were used to investigate the patterns in tracer profiles that arise from different combinations of flows. Field tracer tests were carried out using emplacements of a saline tracer throughout the saturated length of boreholes and also point emplacements at specific horizons. Results demonstrated that SBDTs can be used to identify flowing fractures at the top and bottom of sections of vertical flow, where there is a change in vertical flow rate within a borehole, and also where there are consistent decreases in tracer concentration at a particular depth. The technique enables identification of fractures that might be undetected by temperature and electrical conductance logging, and is a simple field test that can be carried out without pumping the borehole.
|Item Type:||Publication - Article|
|Digital Object Identifier (DOI):||10.1111/j.1745-6584.2010.00708.x|
|Programmes:||BGS Programmes 2010 > Groundwater Science|
|Additional Keywords:||GroundwaterBGS, Groundwater, Environmental tracers|
|Date made live:||07 Apr 2011 10:17|
Actions (login required)