When you think of the Sahara Desert, what’s the first thing that comes to mind? Probably endless, towering sand dunes, right? They’re iconic, but here’s a surprising fact: those sandy landscapes make up a much smaller portion of the Sahara than you might think!
In reality, the Sahara is primarily a rocky desert! Much of it is covered by what scientists call “hamadas” – these are vast, barren stone plateaus, often very flat, with little to no sand. Imagine a giant, rocky table! Then there are “regs,” which are extensive gravel-covered plains. So, next time you picture the Sahara, think rocks and gravel first!
Now, don’t get me wrong, the sand dunes, or “ergs,” are definitely there, and they’re spectacular! These are large areas covered with shifting sand dunes, some reaching hundreds of meters high. The sand itself is mostly tiny quartz grains, eroded from ancient rocks over millions of years and carried by wind. But remember, they cover only about 25% of the Sahara’s surface.
Beyond the rocks and sand, the Sahara also boasts diverse topographical features like rugged mountain ranges, deep depressions, dry valleys called wadis, and even salt flats! It’s a land of incredible variety, far more than just a sea of sand.