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How old is the Sahara Desert?
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Sahara
Sand dunes in the Sahara, near Merzouga, Morocco.
The age of the Sahara is a subject of scientific debate, with estimates varying based on geological evidence:
- Early Estimates: Many studies of regional rock formations suggest the Sahara became established as a desert approximately 2 to 3 million years ago, during the interval spanning the late Pliocene to the early Pleistocene Epoch.12
- Earlier Origins: The discovery of 7-million-year-old dune deposits in northern Chad suggests that the region may have become arid even earlier, during the Miocene Epoch (23 million to 5.3 million years ago).2
Since the Pliocene, the region has experienced repeated climatic oscillations, alternating between arid and humid phases. Most recently, the Sahara underwent a "green period" known as the African Humid Period, which lasted from approximately 11,700 to 5,000 years ago.3