Finite propagation speed for Leibenson's equation on Riemannian manifolds

We consider on arbitrary Riemannian manifolds the Leibenson equation partial derivative(tu) = Delta(p)uq. This equation is also known as doubly nonlinear evolution equation. It comes from hydrodynamics where it describes filtration of a turbulent compressible liquid in porous medium. We prove that that, under optimal restrictions on p and q, weak subsolutions to this equation have finite propagation speed.