Seismic imaging directs an intense sound source into the ground to evaluate subsurface conditions and to detect high concentrations of contamination.

Receivers called geophones, analogous to microphones, pick up “echoes” that come back up through the ground and record the intensity and time of the “echo” on computers.

Data processing turns these signals into images of the geologic structure. This technology is similar in principle to active electromagnetic survey technology.

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