WELLTIE

Quality Well Ties for Better Understanding of Seismic Character

Accurate well-tying and wavelet estimation is a critical step in reservoir characterization. Jason WellTie provides a highly visual and interactive environment for creating, refining and QC'ing wavelets for inversions.
With a proper wavelet, the user can be confident in the results of:

• Seismic Interpretation
• Synthetic Modeling
• AVO Modeling and Analysis
• Deterministic Inversion
• Geostatistical Inversion

Methodology

The well tie process utilizes two key Jason applications that work together: Estimate Wavelets and Well Log Editor. The optimum wavelet is determined to be that which, when convolved with well log reflectivities, results in a synthetic that best matches the input seismic in a least-squares way. The candidate wavelet is further vetted by evaluating its ability to perform seismic inversion on the input traces. Various QCs are available to evaluate its performance.

Key features of the process include:

• AVO/AVA capability by utilizing angle-corrected logs instead of their normal incidence counterparts
• Multi-Well wavelet estimation
• Normal incidence, sub-stack and gather modes
• Input seismic can be angle or offset-based
• Non-white Earth color corrections
• Time shift and dispersive (stretch/squeeze) corrections
• Model-based and interactive dip compensation
• Backus filtering to account for the effects of fine layering
• Constrained sparse spike inversion QC
• Wavelet design window can follow deviated well tracks

Wavelet Estimation Utilities

• Various utilities are available in WellTie to accomplish a wide variety of tasks.
• Wavelet Creation and Editing - Create, Scale and Edit Synthetic Wavelets
• Transform Wavelet (for zero-phasing seismic for interpretation)
• Merge Wavelet Amplitude and Phase Spectra
• Find optimal well position
• Support AVO reconnaissance and analysis
• Wavelet phase rotation analysis, shifting and scaling
• Full waveform synthetic modeling