Submitted by Fehnboi t3_1008551 in explainlikeimfive
I mean, a desert is basically just a huge amount of sand but where does it stop, what is beneath? I googled it and it says there's groundwater but what does that mean, and (how) is that even possible?
Edit: So, actually the main question I wanted to know is if there's a exact border between sand and rock, or if the sand just gets denser and denser until it's rock (but I believe the weight must not be that big), like Saturn or something.
(Yes, I know what a desert is but I specifically need to know about this certain type of desert)