# Dictionary:Instantaneous phase

The instantaneous phase is a seismic attribute, which is independent of trace amplitudes and relates to the propagation phase of the seismic wave front. Conventionally, wave fronts are defined as lines of constant phase, the phase attribute is also a physical attribute and can be used as a discriminator for geometrical shape classification.^{[1]} The equation for instantaneous phase can be viewed as:

where *F(t)* is the seismic trace and *Re F(t)* is the real part of the seismic data *Im F(t)* is the imaginary part of the complex trace.Since, most of the time, wave fronts are defined as lines of constant phase, the phase attribute is a physical attribute and can be effectively used as a discriminator for geometrical shape classifications:

- Best indicator of lateral continuity
- Relates to the phase component of the wave-propagation.
- Can be used to compute the phase velocity.
- Has no amplitude information.
- Sequence boundaries.
- Detailed visualization of bedding configurations.
- Used in the computation of
*instantaneous frequency*and acceleration.

See *Hilbert transform*
See *complex-trace analysis*.

## References

- ↑ Taner, Turhan (1992), Attributes Revisited, Rock Solid Images Houston, Texas (published 2000)