Microcracks in natural granite allow moisture in, combined with the minerals within the granite to ionize the water which becomes conductive enough. The bare granite outcrop on a hill on my property gets struck often.
Unelectrified barns in the old days would get struck by lightning often ... yet they weren't conductive. That's why lightning rods were created, to disperse the stored surface charge so the barn became less attractive to lightning.
Unelectrified barns in the old days would get struck by lightning often...
Something doesn't have to be electrified to be conductive. Not sure why you're making this trash up. Wood is conductive and those barns had metal nails, awnings, hinges, pipes etc. in them That's a completely false comparison.
Microcracks in natural granite allow moisture in
Greater amounts than the water on the ground, or trees nearby (keep in mind nearby means hundreds of feet or more). Pure water isn't conductive. The conductivity in water is due to impurities in such and would require more water than "microcracks" to be of relevance.
The electrical properties of granite appear to be dominantly controlled by the amount of free water in the granite and by temperature. Minor contributions to the electrical properties are provided by hydrostatic and lithostatic pressure, structurally bound water, oxygen fugacity, and other parameters. The effect of sulphur fugacity may be important but is experimentally unconfirmed. In addition to changing the magnitude of electrical properties, the amount and chemistry of water in granite significantly changes the temperature dependence of the electrical properties. With increasing temperature, changes in water content retain large, but lessened, effects on electrical properties. Near room temperature, a monolayer of water will decrease the electrical resistivity by an order of magnitude. Several weight-percent water may decrease the electrical resistivity by as much as nine orders of magnitude and decrease the thermal activation energy by a factor of five. At elevated temperatures just below granitic melting, a few weight-percent water may still decrease the resistivity by as much as 3 orders of magnitude and the activation energy by a factor of two.
https://pubs.er.usgs.gov/publication/70012142
Who's the one making shit up???
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