Seismic Thickness Estimation: Three Approaches - Pros and Cons

Pros and Cons

Method 1: Conventional Tuning Thickness Analysis

Pros:

• User and time intensiveness mandates careful QC.

Cons:

• Two attributes are required to quantify thickness: peak trough time separation for thicknesses greater than the tuning thickness; amplitude for thicknesses less than the tuning thickness.
• User and time intensiveness mandates careful QC and careful seismic event picking.

Method 2: Peak Fequency and Peak Amplitude Mapping

Pros:

• Collapses the volume of the Spectral Decomposition Tuning Cube into two maps.
• Does not require careful seismic event picking when the zone of interest is relatively bright.

Cons:

• Two attributes are required to quantify thickness (aka method 1): peak frequency for thicknesses greater than the tuning thickness; peak energy for thicknesses less than the tuning thickness.

Method 3: Thickness via Discrete Fourier Components

Pros:

• Each thickness/velocity combination exhbits a characteristic expression at each frequency.
• By choosing appropriately low frequency components, the entire range of possible thicknesses falls below the tuning thicknessess, and therefore can be quantified using energy variability.
• Can selectively anayze frequencies exhibitting highest signal to noise ratios.
• Does not require careful seismic event picking when the zone of interest is relatively bright.

Cons:

• Complex flow unit distributions require seismic modeling and spectral decomposition analysis to determine relationship between spectral response and thickness.