Structure Below the Growing Surface
  In recent years there has been a growing interest in the statistical properties of surfaces growing under deposition of material. Yet it is clear that a theory describing the evolution of a surface should at the same time describe the properties of the bulk buried underneath. Clearly, the structure of the bulk is relevant for many practical purposes, such as the transport of electric current in devices, transport of fluids in geological formations and stress transmission in granular systems. The present paper demonstrates explicitly how models describing deposition can provide us with information on the structure of the bulk. Comparison of an analytic model with a simulation of a discrete growth model reveals an interesting long range tail in the density-density correlation in the direction of deposition. 
Eytan Katzav, Sam F. Edwards and Moshe Schwartz