Integrated Project Design

Designing seismic solutions to E&P challenges

The key to unlocking the full potential of seismic data lies in the initial survey design. Through an understanding of the client's reservoir objectives, analysis of log and legacy seismic data, the Integrated Project Design (IPD) process analyses the feasibility and benefits of alternative seismic solutions and delivers to the client the optimum survey design.

A key element of IPD is an evaluation of the subsequent data processing required to provide the necessary interpretation products for reservoir evaluation. The acquired dataset must not only provide for optimally sampled signals; it must also provide adequate sampling of the noise. If this is not the case, aliased energy will remain in the data, leading to loss of resolution and degradation of the final image.

The IPD process:

Reservoir objectives
A new breed of seismic surveys is being designed to meet specific reservoir objectives. In many cases these surveys are for 4D or reservoir management objectives. Whatever the objective, whether it be reservoir delineation, lithology discrimination, fluid contact movement, or others, modeling must be performed to demonstrate the ability of the new survey to meet these objectives.

• Earth model resolution analysis
  Log data, petrophysical data, VSP, seismic data attenuation (Qp, Qs), and velocity information are all used to define the earth model. Seismic source signatures and resultant target reflection wavelets are then modeled to establish theoretically achievable resolution limits. Necessary sampling requirements can then be estimated for any new survey where improved resolution is a key requirement.
  
• Feasibility analysis
  In the search for seismic solutions to reservoir objectives, it is necessary to demonstrate that a solution is geophysically feasible. Feasibility studies are performed that take log data, petrophysical data, and production data to model, for example, fluid replacement scenarios. Such a study can be used to predict if a time-lapse (4D) seismic response is sufficiently well resolved.By using a synthetic wedge model, built by stretching or squeezing zones of interest in log data, the limits of interpretability can be demonstrated. Forward modeling proceeds by convolving the earth model with the anticipated signal wavelet and noise estimation.
  
  Finally, the synthetic seismic sections are inverted to acoustic and shear impedance sections from which the limits of resolution can be estimated. As the full elastic earth response is included, an assessment of appropriate seismic technology can be performed. Towed streamer operations or seabed seismic acquisition are considered and the most cost-effective solutions identified.
  
• Q-Technology benefit analysis
  The Q-Technology method delivers new standards in seismic acquisition. Single-sensor recording and the ability to group form to optimum trace sampling are two such benefits. In the case of Q-Marine acquisition, the ability to steer streamers has introduced a step change in repeatability of 4D operations. The IPD process uses analysis tools to quantify the benefit of using Q-Technology methodology over conventional seismic technology.
  
• Design
  Once a survey is shown to be feasible and the benefits of the appropriate technology demonstrated (e.g., towed streamer, Q-Technology, multicomponent), detailed design of the acquisition, processing, and inversion products can be performed. Acquisition parameters must be designed to meet data processing and inversion product requirements in terms of temporal and spatial sampling, data capture, and noise suppression.