Section view along an arbline traversing a number of different intersecting 2D lines within a single survey. Before conditioning the velocity mis-ties at line intersections are obvious. After conditioning these have all been reconciled producing a consistent, smooth model.
Inputs include marine and/or land 2D and 3D seismic velocities and well-based velocities (such as checkshot surveys or velocity logs). The workflow solves the problems of velocity mismatches at line intersections within 2D surveys and of combining surveys of differing vintages. As a result of variations in acquisition parameters and processing flows overlapping surveys will often show velocity mismatches. These discrepancies are reconciled using DUG’s velocity conditioning workflows. Regional horizons are used to incorporate structural and stratigraphic constraints into the workflow.
DUG’s Geostatistical Velocity Model Scaling workflow calibrates the regional velocity model to wells, resulting in a final product that can be used for a range of purposes. These include depth conversion of seismic data and horizons, initial input to velocity model building workflows, and quantitative interpretation applications, such as low-frequency model building and pore pressure prediction.
Figure 2: Time-slice through a regional 3D model prepared using a number of 2D and 3D surveys. On the left is the 3D model prepared using just the raw data. On the right is after application of the conditioning workflow. All of the mis-ties have now been reconciled producing a regionally consistent, smooth model.
