It seems because of the drought which is making crops turn brown, some areas of the crops are greener than others because of buried objects which are now forming an outline of previously, unknown ancient structures.
Aerial photographs "show marks made when crops growing over buried features develop at a different rate from those nearby." Up close, they're impossible to see. But from the air, a pattern emerges. Other photos and full article is here.

Aerial photographs "show marks made when crops growing over buried features develop at a different rate from those nearby." Up close, they're impossible to see. But from the air, a pattern emerges. Other photos and full article is here.