| Abstract: | Chronology establishment and dating data analyses on lacustrine deposits in northeastern Sahara show that vast fresh lakes existed over there between 9900-2400 a B.P. Especially, great continuous lakes developed and got their maximum extent during the period from 9800 a B.P. to 6450 a B.P. From 6000 a B.P. to 3600 a B.P., the evolution of the lakes experienced a new stage with a property of drastic fluctuations and a periodicity of 600 years, which was the response to the climatic environment changes. On the aspect of the relation between natural environment and the human, the warm humid period in the Holocene was not only a very important time for human development and evolution, but also was a moment for human reproduction and division. On the other hand, this warm humid period was also a distinguished time to natural environment changes, the accumulation of the strong weathered debris and fine materials formed the basements for the formation of the Sahara Desert. |
