by Michael Steinbacher
While hosting a geology tour one year ago, we passed the formation from the link below.
It has layers of dark material that might be coal or shale. The only way to get such vertical layers from a dune would be to have the formation fold after deposition. That seemed possible but something of a stretch. This caused a re-examination of the dune process.
Sand dunes grow with the direction of the wind. Dry sand bounces along the desert and up the windward side of a dune. When the bouncing sand gets to the ridge, the sand falls down the slip face, increasing the size of the dune in the direction of the wind.
If the blowing material was wet, conglomerate (dirt with various sizes of rocks), or molten, it would stick to the windward side and grow up and back into the wind. This now appears to be the process I misconstrued as duning. I was only wrong by 180 degrees.
Standard geology already has a process exactly like the one described above. It’s called “welded tuff”. Red-hot dust from a volcano blows downwind and sticks to an obstruction, growing back and up, into the wind. In many cases, the volcano alleged to have been responsible is no longer there. And in many cases, the distance between the missing volcano and the “welded tuff” is so great that the dust would have cooled, creating piles of dirt instead of molten rock.
The image below shows “welded tuff”. The wind would have been from the left.
According to many legends, the events during the worldwide plague of darkness had conglomerate falling from the sky, not just dry sand. There was a hurricane with torrential rains. The conglomerate was said to be mingled with a river of fire, in some cases glowing red-hot. This might have been similar to the aurora. A sufficient increase in current density could push the glow mode of an aurora along the surface into a “river of fire” in arc mode. When the current density of the process increased, it appears, a “river of fire” was seen.
I now believe the formations in the images above were both produced by the “welded tuff” process.
The link below is to a Thunderbolts Forum post. It implies that many formation of varying types of rock were produced this way.