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coherence

1. n. [Geophysics]
A measure of the similarity of two seismic traces.
2. n. [Geophysics]
The quality of two wave trains, or waves consisting of several cycles, being in phase.
See: wave
3. n. [Geophysics]
The similarity of two mathematical functions as evaluated in the frequency domain.
4. n. [Geophysics]
A quantitative assessment of the similarity of three or more functions, also called semblance.