Having a reasonable expectation of finding well water prior to drilling a well is a great benefit for the prospective well owner. Southwest Groundwater Surveyor uses the seismoelectric method for locating the optimal well drilling location.
Briefly, the seismoelectric method, sometimes called electroseismic or Electro Kinetic Seismology (EKS) makes use of a phenomenon, known since the 1950’s, whereby an electrical signal is produced when a seismic wave encounters water within rock pores, such as is the case for an aquifer. Although the basic Physics of the method has been understood for many years, and numerous field demonstrations have been completed showing the feasibility of the method, it was not until 1996, when a company called Groundflow Ltd. and later AqualocateLLC developed and patented very specific electronics and associated techniques required to measure and interpret the EKS signal, making the method more practical. Whereby using these techniques, the EKS signal is recorded using a data recording geometry that significantly minimizes naturally occurring electrical noise. Groundflow Ltd developed the instrumentation to both record this signal and to process the data. Therefore allowing the existence of groundwater, (if present) to be inferred along with estimates of the depth and the yield of the aquifer.
Accuracy of interpretation of groundwater data may often be increased if a local well is available where the aquifer depth, thickness and flow rate are known. In this case a sounding can be conducted close to the well, which gives us a better velocity and acoustic attenuation model for the particular underlying rock matrix.
The ideal conditions for a groundwater survey are as follows...
- Access to the desired test sites on the property by a 4 wheel drive pickup truck.
- Survey sites must be at least 50 feet away from underground high voltage lines.
- Surveyors must be able to penetrate the ground surface to a three foot depth.
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