This book presents a study that establishes a set of diagnostic parameters for characterizing the behavior of a geological medium stimulated by external fields and their interactions as a physical basis for developing new methods in exploration geophysics. It describes in detail the investigation methods and instruments (including laboratory, field and borehole devices), and discusses experimental, field and modeling investigations of the interaction of mechanic/electromagnetic fields in reservoir rocks. Lastly, the book also evaluates and the proposed methodology and demonstrates its effectiveness using case studies in which certain geophysical diagnostic/exploration problems have been solved.