Impact of Rocks and Minerals on Underground Magneto-Inductive   Communication and Localization
  In this paper, we analyze the effect of different underground materials on very-low and low frequency magnetic fields used in the contexts of magneto-inductive localization and communication applications, respectively. We calculate the attenuation that these magnetic fields are subject to while passing through most common rocks and minerals. Knowing the attenuation properties is crucial in the design of underground magneto-inductive communication systems. In addition, we provide means to predict the distortions in the magnetic field that impair localization systems. The proposed work offers basic design guidelines for communication and localization systems in terms of channel path-loss, operation frequencies and bandwidth. For the sake of the reproducibility of the results, we provide the raw data and processing source code to be used by the two research communities. 
Traian E. Abrudan and Orfeas Kypris and Niki Trigoni and Andrew   Markham
physics.geo-ph