ISSN:
1745-6584
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Energy, Environment Protection, Nuclear Power Engineering
,
Geosciences
Notes:
Slug and bailer tests are being used increasingly to evaluate the hydraulic properties of “tight” geologic units. Although these pulse methods of stressing a system are used typically only on single wells, the repeated pulse method described here stresses the system in the same manner, but the response is measured in observation wells. This type of pulse test yields much the same information as conventional pumping tests, but it is easier to perform in very low permeability units.The observation well response hydrographs are analyzed by curve-matching techniques. In general, a unique set of type curves must be computed for each pulse test. These type curves are computed easily if the pulsed well is treated as a line-source (or sink). The accuracy of the value of transmissivity (T) determined from the line-source type curves compared to using the finite-diameter well solution depends both on the pulsed well radius (rc) and the time interval between pulses (Δt). If TΔt/rc2 is maintained greater than 50, then T determined from the line-source solution will be within 25% of that determined from more accurate, but computationally inconvenient, finite-diameter well type curves.The repeated-pulse test technique was applied to an experimental well array completed in the Conasauga Shale Formation at Oak Ridge National Laboratory. Values of transmissivity determined by the repeated-pulse method agreed well with the results of slug tests performed on each well individually, and in addition, provided information on storage coefficients and anisotropy at the site.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1745-6584.1982.tb02749.x
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