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Eastern Sahara has been an interesting
study object for the specialists who search for the history of
this place. There were assumptions about an important pluvial
event that could have happened between 6500 and 2500 years BC.
These assumptions were confirmed by some fossils from a lake
sediments dating from the Holocene epoch that were discovered
recently. What today are hyper arid area with no plants, once
were regions of desert grassland and savanna. In the Sudan's
North-West were found about 500 kilometers of vegetation from
the Holocene period. There were analyzed the salient features
from the Southern and Northern sites that were discovered as
well as the pollen of these sites in order to show that in the
Eastern Sahara existed a gradient cover with vegetation. The
fact that in its prehistoric times, the Eastern Sahara had water
resources from the rainfalls or from rivers was shown by some
researches that were made regarding the Sahara wet condition
in the prehistoric times. The data revealed the existence of
three dry river courses with a width that varies from 8 to 20
kilometers. The existence of the water sources in the
prehistoric Sahara allowed to the man, animals and plants to
exist in the Eastern Sahara of those times. The existence of
these dry river courses also explains the oases` presence in
such a hyper arid zone. The origins of these rivers are in the
Sahel's sub-Saharan belt or the Sahara's massifs. It seems that
the last time when these rivers were flowed with water was
during the pluvial event we were talking about in the beginning
of this article. Life and death in the Eastern Sahara were
brought by the alternation of the wet periods with the dry
periods, as well as the fauna and flora`s modifications. |
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