They form in the ocean where undersea volcanoes are errupting. The magma turning into lava piles up on top of itself over lots of time to form land.
Quicksand is mainly water and sand so it makes sense that it eventually leads to a water source underground.
Instead, they packed the earth, which is rich in clay, into thick walls that provided insulation from the hot summers and cold winters.
Explanation:
hope that helped :)
