Figure 16-39 shows a cross section of the upper layers of the Earth. The surface of the Earth is broken into several rigid blocks, called plates, that slide (slowly!) over a “slushy” lower layer called the asthenosphere. See the figure for typical dimensions. Suppose that the speed of the rigid plate shown is v₀ = 48 mm/y, and the base of the asthenosphere does not move. Calculate the shearing stress (shearing force per unit area) on the base of the plate. The viscosity of the asthenosphere material is 4.0 × 10¹⁹ N∙s/m². Ignore the curvature of the Earth.

Radhika Batra , 9 Years ago

Grade 11