Depth conversion services
Aker Solutions has established a Centre of Excellence for depth conversion, staffed by experts, for the purpose of providing a high quality depth conversion consultancy service at competitive prices for internal and external customers. This is a long term commitment, which involves investments on our part in personnel, methods, software and customer relations.
Our team has more than 20 years experience as specialists in depth conversion in major oil companies. They have worked mainly on the Norwegian continental shelf, but also internationally offshore and onshore. They have a lot of experience with depth conversions that are technically difficult or have large impact on business decisions, such as in regional exploration where source rock maturation is critical, or in field development where reliable volume and uncertainty estimates can be critical for viability, or in unitisation and redetermination.
Recommended depth conversion methods that are available from Aker Solutions
Regional play and petroleum system evaluation
- Regional time slice velocity cube with stacking velocities and check shots
- Well velocity functions in deeper layers where the stacking velocities are poor
- Uplift and erosion estimates from velocity inversion
- Experience based hi-case lo-case uncertainty estimates
Prospect evaluation
- If time is short, go with a regional time slice velocity cube
- If not, run a series of sensitivities, with different stacking velocity and function methods
- Pick the most likely case, use the others for depth uncertainty and volume risk
- Do a peer review and look for pitfalls
- Field development and PDO preparation
- In-depth study of all relevant data, find and fix problems
- Compare with seismic attributes, spend time with the data, understand them
- Develop the best possible deterministic case, often a combination of horizon keyed stacking velocity depth conversion from Seabed to near top reservoir, and velocity functions below
- Use stochastic modeling to calculate P10 - P50 - P90 depth uncertainties and gross rock volume estimates
Field operation
- Emphasis on well velocity data analysis; regression, variograms, kriging
- Quantitative depth and depth uncertainty estimates for well prognoses
- Time conversion of proposed well paths
- “Least risk” locations for new production wells
- Depth conversion of fault sticks
- Depth conversion under fault planes
- Velocity models for map migration, seismic inversion and PSDM
Unitisation and redetermination
- Velocity data management, data base QC and verification
- Calibration & first break to trough correction of velocity logs
- Synthetic seismograms and well tie
- Best practice deterministic depth conversion
- Evaluation / risking of alternative cases