1. n. [Geophysics]

Seismic data acquired in a land, marine, or borehole environment by using more than one geophone or accelerometer. 3C seismic data, a type of multicomponent seismic data, uses three orthogonally oriented geophones or accelerometers. 4C seismic data, another type of multicomponent seismic data, involves the addition of a hydrophone to three orthogonally oriented geophones or accelerometers. 3C multicomponent seismic data is particularly appropriate when the addition of a hydrophone (the basis for 4C seismic data) adds no value to the measurement, for example, on land. This technique allows determination of both the type of wave and its direction of propagation.

See: accelerometer,  four-component seismic data,  geophone,  three-component seismic data