They were build over a millennium, beginning about 4,700 years ago.
This could improve the protection measures of Egyptian cultural heritage.
They propose dubbing the ancient branch Ahramat, Arabic for pyramids.
The Pyramid of Khafre in Giza.Photo: DeAgostini (Getty Images)
Archaeologist Eman Ghoneim from the University of North Carolina Wilmington led the research.
But thanks to radar imagery and sediment coring, an ancient resource of the Egyptians has come to light.
News from the future, delivered to your present.
A map showing the placement of the ancient river branch.Graphic: Eman Ghoneim et al.
