Thank you for your questions regarding seismic waves and electrode spacing, it is our pleasure to help.
In regards to testing the earth resistivity, we are not aware of any terminology associated with DSR & TSR. However, Geologists do use the terms DSR &TSR when dealing with seismic wave analysis when they calculate the velocity of a wave during a Seismic Refraction Survey. DSR stands for “Distance from Source to Receiver” and TSR stands for “Time from Source to Receiver”. By setting up at least two receivers at a known distance, the time differential of when the wave strikes the receivers can be used to calculate the velocity of the wave.
In regards to your question of probe depth during a earth resistivity test, the probe depth should be as shallow as possible to get a reading. Keep in mind that the probes have a sphere of influence and a large sphere of influence can adversely impact the results of the test. The rule is to drive the probe into the earth only as deep as is needed to get a good signal. In fact, some people use heavy plates or chain that is simply laid flat on the earth so that there is no penetration into the soil at all. You are much better off using a little salt water around the probe, than you are driving the probe down deeper into the earth. Also, you must make note of the depths of the probes as the computer systems that will analyze the data can accommodate for the various different penetration depths.
We hope that this answers your questions. Please feel free to contact us again should you have any further questions.
The Engineering Team at E&S Grounding Solutions
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