The age of the integrated Nile is based on two different hypotheses. One is that the Nile’s integrated drainage is relatively recent and that the Nile basin was previously divided into a number of distinct basins, only the most northern of which fed a river that now flows through Egypt and Sudan. According to Rushdi Said’s theory, Egypt supplied the majority of the Nile’s waters in its early history.
Another theory asserts that the Egyptian Nile was used to transport water from Ethiopia’s Blue Nile, Atbara, and Takazze rivers to the Mediterranean well into the Tertiary period.
Salama suggests that a series of distinct closed continental basins each occupied one of the major parts of the Sudanese Rift System during the Paleogene and Neogene Periods (66 million to 2.588 million years ago): Atbara rift, Mellut rift, White Nile rift, Blue Nile rift, and Sag El Naam rift are all rifts. At its center, the Mellut Basin is nearly 12 kilometers (7.5 miles) deep.
There has been tectonic activity at the northern and southern boundaries of this rift, suggesting that it may still be active. It’s possible that the Sudd swamp, which is in the middle of the basin, is still sinking. Although it is shallower than the Bahr el Arab rift, the White Nile Rift system is approximately 9 kilometers (5.6 miles) deep. The depth of the sediments in the Blue Nile Rift System, according to geophysical research, is 5–9 kilometers (3.1–5.6 miles). The rate of sediment deposition was sufficient to fill and link these basins, which were not connected until their subsidence ended.
During the current phases of tectonic activity in the Eastern, Central, and Sudanese Rift systems, the Egyptian and Sudanese Niles connected to capture the Ethiopian and Equatorial headwaters. The association of the various Niles happened during cyclic wet periods. The Atbarah spilled over shut bowl during the wet time frames happened around 100,000 to quite a while back.
During the wet period that lasted from 70,000 to 80,000 years B.P., the Blue Nile joined the main Nile. Until the connection of the Victoria Nile to the main system around 12,500 years ago, during the African humid period, the White Nile system in Bahr El Arab and the White Nile Rifts remained a closed lake.