Whilst there are significant benefits there are also limitations. It is necessary to have good quality input data as the quality of the output is governed by this. With good quality seismic data which matches the well data then it may be possible to get excellent outputs. However, it must be remembered that seismic data has limited frequency content therefore it will not be possible to produce a meaningful broadband output beyond a certain point. In the case of really thin beds these high frequency events cannot be resolved within the seismic bandwidth. Furthermore, using seismic alone, it will not be possible to resolve the low-frequency trends and for absolute impedance it will be necessary to input a geological model. Whilst it may be possible with a good quality input data to get a quantitative output, these methods are complex, requiring skilled specialists. Such methods are time consuming and can be a source of error.

Whilst using good quality input data is always desirable, using poorer quality data can give very usable results. A qualitative or semi-quantitative inversion may yield significant benefits on any data and it is much easier to achieve and is less error prone. Frequently taking this approach is sufficient and can be done by a non-specialist within a much shorter time scale.

Before embarking on a Frequency Shaping project it is important to investigate any well log data that is available. It is recommended the frequency content required to image the target is investigated.

Estimate the frequencies available within the seismic by wavelet estimation or spectral analysis.

A good feasibility analysis can be performed by applying a bandpass filter to the well impedance and reflectivity data. The selected frequency cuttoffs should be the same frequencies as desired in the output seismic data. As a rule of thumb use 15dB down point as limits. If the target’s boundaries are improved then the frequencies should be acceptable.

It is very important not to stretch too much the seismic bandwidth. Adding frequencies that were not recorded in field is not desired. (Note: this can be very risky - you get what you add).