Changes

* s = rock surface area (surface area of grains in cross section A)

* s = rock surface area (surface area of grains in cross section A)

<math>k = [0.2 \times φ^3] / s^2 \times (1 - φ^2)</math>

<math>k = \frac{(0.2 \times φ^3)}{s^2} \times {(1-φ)^2}</math>

==Buoyancy pressure==

==Buoyancy pressure==