A methods and apparatus for the detection and exploration of buried objects and hydrocarbons uses two separate signals having different frequency characteristics combined to enable interferometric analysis and imaging systems including radar, sonar, seismological, and general acoustical systems. The measurement and analysis of absorption and other elastic moduli are derived from a three-dimensional display of interferometric information. Interferometric holography also employs the unique characteristic record of frequency, phase, and amplitude of more than one signal.