Eman Ghoneim
Researcher Eman Ghoneim studies the surface topography of the extinct part of the Nile River located in front of the Pyramids of Giza and the Great Sphinx.
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Egypt's Great Pyramids and other ancient ruins at Giza sit on an isolated piece of land on the edge of the Sahara Desert.
This inhospitable site has long puzzled archaeologists. They found evidence that the Nile River once somehow flowed near these pyramids, facilitating the construction of the landmarks that began 4,700 years ago.
The new study, published Thursday in the journal Communications Global Environment, used satellite images and analysis of sediment cores to examine the 64-kilometer-long (40-mile) stretch of dry land, long buried beneath farmland and desert. Created a map of the Nile River tributaries. .
“Although many efforts have been made to reconstruct the early Nile waterway, most have been limited to the collection of soil samples from small sites, and therefore only a fragmentary portion of the ancient Nile waterway has been reconstructed. “This led to the creation of maps,” said the study's lead author. Eman Ghoneim is a professor and director of the Space and Drone Remote Sensing Laboratory in the Department of Earth and Ocean Sciences at the University of North Carolina at Wilmington.
“This is the first study to provide the first map of a long-lost ancient tributary of the Nile.”
Ghoneim and his colleagues call this extinct tributary of the Nile River Ahramat, which means pyramid in Arabic.
Eman Ghoneim et al.
The ancient Egyptians are thought to have built many pyramids using the now extinct Ahramat tributary.
The ancient waterway was thought to have been about half a kilometer (about a third of a mile) wide and at least 25 meters (82 feet) deep, similar to the modern Nile, Ghoneim said.
“The large size, length, and proximity of the Ahramat tributary to the 31 pyramids in the study area strongly suggests that it is a very important functional waterway,” Ghoneim said. .
He said the river would have played an important role in helping the ancient Egyptians transport the huge amounts of building materials and labor needed to build the pyramids.
“Our research also shows that many of the pyramids in the study area have causeways, elevated ceremonial walkways that run perpendicular to the course of the Ahramat branch and end directly on the riverbank. .”
Eman Ghoneim
The Red Pyramid in the necropolis of Dahshur is located near a defunct tributary of the Nile River.
Ghoneyim said no trace of the river can be seen in aerial photographs or images from optical satellites. In fact, while investigating extensive radar satellite data of ancient rivers and lakes, she only discovered something unexpected that could reveal a new groundwater source.
“I'm a geomorphologist and a paleohydrologist who studies landforms. I have that kind of trained eye,” she said.
“While working with this data, we noticed this very obvious tributary, or kind of riverbank, but it was so far away from the Nile that it didn't make sense,” she added. .
Ghoneim, who was born and raised in Egypt, is familiar with the region's pyramids and has always wondered why they were built there. She applied to the National Science Foundation for further investigation, and geophysical data taken on the ground using ground-penetrating radar and electromagnetic tomography confirmed it to be an ancient Nile tributary. . Two long soil cores extracted by the research team using a drilling rig revealed sandy deposits consistent with river channels approximately 25 meters (82 feet) deep.
According to the study, “innumerable” temples may still be buried under farmland and desert sand along the banks of the Ahramat tributary.
Eman Ghoneim
The researchers collected soil samples to confirm their findings.
It is still unclear why this tributary of the river dried up or disappeared. Periods of drought and desertification likely pushed sand into the area, silting the river, Ghoneim said.
Nick Marriner, a geographer at the French National Center for Scientific Research in Paris, said the study demonstrated that the topography and river landscape of the Nile at the time the pyramids were built was very different from today. . Although he was not involved in this study, he has conducted research on the history of Giza's rivers.
“This study completes an important piece of the landscape puzzle of the past,” Mariner said. “By putting these pieces together, we can see what the Nile floodplain looked like during the time of the pyramid builders, and how the ancient Egyptians used the environment to transport building materials for their monument-building efforts.” You get a clearer picture of how you use it.”
Eman Ghoneim
The research team stands in front of the Valley of Unas Temple, which would have served as a river port in ancient Egypt.
