the rock pinging similar to when comets explode or when we hit them with a metal object like deep impact on Tempel 1? I wonder what sort of "note" it might have produced? has there been any other recordings of comets when they break up?
Could the ping have been creating by back EMF? These superdeep boreholes show that there are very defined conductive / non conductive layers in the ground. If one is charged up and the rock comes along could it discharge that layer so creating the counter EMF? Even if it is a small current the back EMF can be huge. Although i guess the casing of the pipe would cancel that out?
i found another pdf that is similar that seems to explain the electrical testing in more details and also has some examples of results
borehole logging in hydrogeology (pdf)This is another pdf but is purely about electrical measurements -
Cross Borehole Electrical Resistivity Tomography (ERT) Measurements (pdf). It also gives measurements of the resistivity of materials. If our geology was created by the Electric Universe then a materials or areas resistivity may create the distinct minerals in that area. I think of it like bulbs that have different resistance so are hotter/colder/brighter.
Is resistivity another part of the reason why you get slight variations of the same types of things? Why one area might either attract the forces or be uplighted into mountains or become a grand canyon?
This is also interesting in a couple of ways to do with the hollow earth theory and the EU circuits in the earth perhaps forming our oil.
"•An air filled void will always appear as a high resistive body.
•A water filled void will appear as a less resistive body than an air filled void of the same size.
Note that distilled water has very high resistivity and gradually becomes more conductive (less resistive) with more dissolved solids. Therefore resistivity can be used as a measure of the quality of ground water. The resistivity method is therefore a very good method for mapping salt water intrusion in coastal areas. In a similar way, water with a degree of in-organic and some organic pollutants, will gradually become less resistive with higher concentrations of pollutants.
Frozen water, i.e. ice has a very high resistivity. The resistivity method is therefore very good for mapping permafrost (permanently frozen subsoil) in arctic areas.
Organic compounds like hydrocarbons typically have very high resistivity. However, some scientists have been reporting observation of a conductive zone where hydrocarbons in the ground interface with ground water. It is believed that this effect may be dependent on bacterial activity on the hydrocarbons at the water/hydrocarbon interface. It is therefore expected that hydrocarbons will show up as high resistive areas, maybe in connection with conductive areas.
Cross Borehole Electrical Resistivity Tomography (ERT) Measurements (pdf)"