Investigating The Resolution Of Resistivity Arrays Using Inverse Theory

We used a fast 2-D minimum structure inverse solution to examine the ability of different<br>resistivity arrays to resolve structures given noisy synthetic data. We found that the resistivity<br>models obtained from inversion of the dipole-dipole data were usually very similar to the estimated<br>models from pole-dipole data, and both were superior to estimated models from pole-pole data.<br>This is because noisy dipole-dipole or pole-dipole data define geoelectric structures much more<br>precisely than an equivalent set of noisy pole-pole data. One structure where the dipole-dipole<br>array appeared decidedly superior was the prism beneath a conductive overburden. The final<br>estimated models from the pole-pole data were more poorly resolved than the final models from the<br>other arrays. Our results show that the pole-pole data is a poor choice if vertical resolution of a<br>geoelectric structure is crucial. Furthermore, if pole-pole data contains even a fraction of a percent<br>of noise, the transformation of such data through superposition to equivalent data of other array<br>types is virtually impossible, and significant information is lost.