A Customer Comparison of Passive Cables

Background

An AGI customer experienced data quality issues when they used Third-Party cables. They decided to replace 28 of their 56 electrodes with the AGI FlexLite Passive Electrode Cable and do a comparison test between the two brands. This test was done on a site in the Mid-Atlantic, USA in May 2017.

Process

The customer used a SuperSting™ R8 with SwitchBox28™, fully-charged deep-cycle marine battery, stainless-steel stakes, and AGI EarthImager™ 2D software for data inversion. The AGI cables used were two-year-old FlexLite proprietary cables with 28 total electrodes spaced at 6ft/1.83m. The undisclosed Third-Party cables were three-year-old passive cables with 28 total electrodes spaced at 6ft/1.83m. All comparison inversion models used the same parameter sets with identical stop criteria and histogram data removal thresholds. Any variations in RMS, L2 or numbers of iterations are related to the amount of noise and spikes.

Results 

The customer found that AGI FlexLite Cables measured significantly cleaner raw data with less spikes. The AGI FlexLite Cables produced no spikes and 100% of the raw data was retained. The Third-Party Passive Resistivity Cables showed 12 spikes, or 3% of the raw data that needed to be removed.

Models from the AGI data also converged faster and with lower RMS error and better L2-Norm and contained more good data in the final model. Ultimately, no filtering was required to get the final model with the FlexLite cables. Significantly more data needed to be removed with the Third-Party Passive Cables. It took 12 model runs and 55% data removal to fit a good model.

The two final models shared similar features, but there were many more clear artifacts in the Third-Party Passive Cables data.