Carbomer-based gel to improve contact resistance in Electrical Resistivity Tomography (ERT)

[ignapozo]

Hi everyone, I'm here at a new job.

One of the tasks I was given is to improve the process related to electrical resistivity tomography (ERT), specifically, to improve the contact resistance.

One of the options I found was to make use of carbomer-based gel, how useful can it be? is it worth buying?
Considering that 1kg costs approximately 35 usd

I look forward to hearing from you.

[geophix]

We use salt water, much cheaper.

[ignapozo]

Thank you for your fast response!
I had already read about the option of using salt water, but many of the work areas are hard rocks, with boulders, and water may not be very useful there due to the porosity of the surface.
What could be used in case where the materials have a lot of air-filled pore spaces and these are in contact with the electrodes?
Will the bentonite work well?

[geophix]

If you drill into the rock and mix the dust with salt water, I think it would work.