Science 10

When particles of sediment and gravel are sorted by size, the porosity of the soil is at its greatest. Water can easily flow through the uniform spaces created by the layering of distinct sizes of particles, increasing the permeability of the soil and allowing more water to penetrate deeper layers.

Students examined the effects of sorted and unsorted particle layers on porosity and permeability.

Activity 1

Student randomly dropped various sized beads (ranging from 10 mm diameter to 50 mm diameter) into a glass cylinder. The top of the cylinder was labeled A, and the resting point near the bottom of the cylinder was labeled as B for each bead. They then recorded how long it took for water to reach the bottom of the cylinder in an effort to measure porosity and permeability.

Activity 2

The students repeated the procedure detailed in Activity 1 except that the beads were placed in the cylinder in order of increasing diameter.