Modeling the Viscoelastic Behavior of Quartz and Clay Minerals in Shale by Nanoindentation Creep Tests

Figure 9

Linear regressions for employing Burger’s model for quartz and clay minerals at various peak loads. Fitting parameters: (a) E₁, (b) E₂, (c) η₁, and (d) η₂. Error bars are one standard deviation.

(a)

(b)

(c)

(d)