Interesting discussion on the possible uses of ancient terra preta.

I listen to this podcast all the time.  Some far out there ideas on some stuff, but it really gets me thinking.

Starting at about 47:20 going on for about twenty minutes or so.  https://www.earthancients.com/?portfolio=jared-murphy-its-not-aliens-its-us-part-2

Nano technology
Communication
Power transmission
Carbon dioxide filter
Heavy metals filter
Nutrient dense soil
Foundation support

"genius dirt"

and if that's interesting later on in the podcast they go on to speak of ancient megalithic building be made from geo-polymers.