Attribute Description: One piece of information we can extract is the locations where instantaneous frequencies jump or go in the reverse direction. As we have discussed earlier, these jumps are indicative of closely arriving reflected wavelets. Therefore, the time derivative of the phase function will contain the indicators for thin beds, in the form of large variations of instantaneous frequency. Its smooth variation will relate to the bedding characteristics, which we will have to investigate further.
Interpretation Use: This attribute shows the interference zones in phase. It is a physical attribute since it relates to closely spaced events. It can be used in detailed studies
- Can indicate overlapping events
- Indicates thin beds, when laterally continuous
- Indicates non-reflecting zone, when it appears laterally at random, like ‘salt and pepper’
- Shows fin detail of bedding patterns
Since the distribution of this data is Gaussian in nature, normal seismic colorbars of preference can be used.
Computation: The thin bed indicator is, therefore, computed as the difference between the instantaneous and the time-averaged frequencies:
- Taner, M. T., 2001, Seismic attributes: Canadian Society of Exploration Geophysicists Recorder, 26, no 7.