13 Seismic

A seismic survey is an organization of seismic lines. In the context of RESQML, a seismic survey feature does not refer to any vertical dimension information, but only areally at shot point locations or common midpoint gathers. However, vertical coordinates may be transferred as part of the seismic coordinate geometry.

The seismic traces, if needed by reservoir models, are transferred in an industry standard format such as SEGY. The SEGY format contains information about the number of samples in the seismic traces and whether the vertical domain is in time or depth. This section only discusses the areal aspects of seismic surveys.

RESQML supports two basic kinds of seismic surveys:

• seismic lattice (organization of the traces for the 3D acquisition and processing phases).
• seismic line (organization of the traces for the 2D acquisition and processing phases).

Additionally, to transport several 3D seismic surveys or seismic lines of one or more 2D seismic surveys together:

• 3D Seismic lattices can be aggregated into a seismic lattice set (3D survey set), if needed.
• 2D Seismic lines can be aggregated into a seismic line set (2D seismic survey or surveys) in the same way.

Thus there are four seismic survey features that are represented in RESQML as follows:

• A seismic lattice is generally represented using a grid 2D representation.
• A seismic lattice set is then represented by several grid 2D representations.
• A seismic line is generally represented using a polyline representation.

• The seismic line set is then represented by several polyline representations.

For more information on representations, see 6 Representations (Shared Concepts) .

In RESQML seismic surveys are technical features that do not have multiple interpretations. Although it is possible to re-interpret a seismic survey for improved physical properties or for positioning, these types of relationships are not included within the RESQML knowledge hierarchy. (For more information on the knowledge hierarchy, see 5 Knowledge Hierarchy : Features, Interpretations, Representations , and Properties .)