The image below shows what patterns form when material is sifted
onto a surface that has been exposed to an electric discharge.
Contrast this to what is seen at the point of a lightening strike and we should ask: Were some details washes or blown away following the discharge? Would lofted material gathered back to the discharge path if conditions would have permitted such undisturbed activity? We may only determine this by carefully conducted experiments at smaller scales or even at large scale, providing the room is large enough.
The method for forming the patterns above
are reproduced in part in the image below.
Additional details about this experiment have been scanned to the following jpegs:
Note that in paragraph 384 chalk is used and the result is a finer feathery feature at the discharge path.
You can see similar results throughout the features presented in ess-crt11
and elsewhere in electric-spark-scars.com, especially where fiberglass powder was used.
Many of these images show the depositing side of the process but the excavation aspect has been demonstrated as well. With various experiments such as: The Two CRT pass-over monitor experiment, Ridge groove and dome experiments-ess-crt11 and 12, and several others where single point discharges show the radial patterns formed, but when the probe is in motion, strings of spiders show the clustering of features which might lend itself to replication of dendritic accumulation at the rim of the excavation path as material is redeposited electrostatically.
Throughout the crater and crater chain pictures pay special attention to rim features. There is good reason to expect that those will re-occur as the probe moves across the surface more quickly discharging each area as it goes and setting up surface conditions for material re-deposition electro-statically.