Normally, the soil on the bottom. Gross density is higher than the Earth, is now on the ground there now due to the lower quantity of particle size of clay over and over from the weight of pressure now on the ground.
Typically, the lower soil A density higher than the upper soil. Due to the lower amount of soil over clay. The pressure from the weight of the upper soil.
Usually the lower soil density, higher total soil in the upper Due to lower volume of soil particle size of clay. And pressure from the weight of the soil in the upper