Why is there so much sand in sahara?

Question

Why is there so much sand in sahara?

Answer 1

According to El-Baz and others, (1999 and unesco site) the mostly quartz sand of the eastern Sahara was  brought in by northward flowing ancient river systems and was deposited in low areas with ancient lakes. During dryer times, winds picked up the sands and redeposited the grains as sand dunes and sheets.

The hypothesis that the sand was brought in by ancient river systems rather than by wind erosion of northern mountains is important because it may indicate the presence of groundwater deep beneath the desert surface.

Answer 2

because its a dessert.... it has alot to do with the fact that farmers brought a lot of cattle into the area and they killed the ecosystem. but that was a long time ago. Now its just one of the largest desserts in the world. Antarctica being the largest.... Yes it is a dessert. look it up

Answer 3

Desert landscapes are mostly moulded by the wind but water has also played its part. many deserts including the Sahara once had climates that were far more moist than they have today. deserts are often completely dry for several years, but many centimetres of rain may fall in a few hours during one freak storm.

the chief agent of erosion, transportation and deposition in deserts is the wind. wind-blown sand polishes rocks and cuts low caves in cliffs. in many deserts wind-blown sand carves out deep hollows.