<P> The Steinberg - Cochran - Guinan (SCG) shear modulus model is pressure dependent and has the form </P> <Dl> <Dd> μ (p, T) = μ 0 + ∂ μ ∂ p p η 1 / 3 + ∂ μ ∂ T (T − 300); η: = ρ / ρ 0 (\ displaystyle \ mu (p, T) = \ mu _ (0) + (\ frac (\ partial \ mu) (\ partial p)) (\ frac (p) (\ eta ^ (1 / 3))) + (\ frac (\ partial \ mu) (\ partial T)) (T - 300); \ quad \ eta: = \ rho / \ rho _ (0)) </Dd> </Dl> <Dd> μ (p, T) = μ 0 + ∂ μ ∂ p p η 1 / 3 + ∂ μ ∂ T (T − 300); η: = ρ / ρ 0 (\ displaystyle \ mu (p, T) = \ mu _ (0) + (\ frac (\ partial \ mu) (\ partial p)) (\ frac (p) (\ eta ^ (1 / 3))) + (\ frac (\ partial \ mu) (\ partial T)) (T - 300); \ quad \ eta: = \ rho / \ rho _ (0)) </Dd> <P> where, μ is the shear modulus at the reference state (T = 300 K, p = 0, η = 1), p is the pressure, and T is the temperature . </P>

The dimensional representation for modulus of rigidity is given by