this is the vimeo video that started it.
Ancient Irrigation of South Africa
from Gary Schoenung 1 year ago
The Okavango delta in South Africa is surrounded by evidence of hundreds of miles of artificial irrigation. The parallel channels that you see are a mile or so apart. This suggests that there was once an extremely large population there utilizing advanced agricultural techniques. (VIDEO UPDATED September 8 2013)
It’s one of a series of 10:
http://vimeo.com/user12206452/videos
After looking at the low angle, 5 minute video of the “irrigation” ditches, I am even more convinced that these are not sand dunes. You simply do not find sand dunes regularly arranged on either side of a narrow feature, then a regular wide feature before the next cluster. Also, the soil colors appear to be similar on each side of the ditches as digging and throwing up embankments would cause. I noticed a number of whitish areas, would those be salt contamination of the soil?
I looked at several of the other videos you posted. I am inclined to think that the “wall” in Wisconsin is natural splitting of rock, he really did not show enough area to clarify conclusions. The Australian “pyramids” were interesting. Unlike the photos of the Egyptian and Mexican pyramids, it was hard to see elevated terrain features. I think a more like source is south Asian settlers, the forms seem more similar. Also there are enough of them to conclude they are not a natural phenomenon. Cheers, and I plan to continue looking at the Okavango situation and hope some serious archaeology gets funded soon for that area.