Superdispersion in homogeneous unsaturated porous media using NMR propagators

Accepted

The NMR propagator technique allows the measurements of the variance ��2=<(��-<��>)2 > of the displacements as a function of time t when flowing in a porous media. The time dependence of �� is a very sensitive test of Gaussian behaviour compared to the analysis of the shape of propagators. Super-dispersion is occurring when �� 2 ��� t�� with the exponent �� larger than 1. In a homogeneous 30 ��m grain pack and 10