Publications

The review of the past six years of in-house experience with acquisition feasibility studies has shown the significant benefits derived from this type of study. These are performed using a common methodology whether for land, transition or marine surveys.Put simply, a typical feasibility study goes through several steps : after a reconnaissance trip to the survey area and collection of information about local constraints, the main point of focus is to simulate three dimensional (3D) data (using 3D geometries and available 2D data, or 3D modeling) to assess the impact of modifications to various acquisition parameters complying with the defined survey objectives and operational criteria. Processing in 3D mode is applied to the modeled 3D data, including 3D Dip Move Out (DMO), de-multiple and migration. Evaluation of the simulated data is carried out using different techniques such as difference sections and the definition of data quality thresholds. At this stage, cost simulations are powerful decision-aid tools. Ranking of the proposed geometries and parameters is based on technical and financial merits.Originally, these studies were carried out for land surveys but were then extended to the infill requirements for marine surveys. Infill is caused by the impact of currents on streamer geometry and the resulting gaps in the fold of coverage. The improved methodology resulted in a better control of seismic quality, processing requirements and a reduced amount of infill.The impact of these studies can be enhanced when using criteria familiar to interpreters. This involves a full integration of the feasibility chain, from modeling tools to workstation through a true 3D processing package. The interaction between acquisition geophysicists and interpreters will then be facilitated.