Seismic Base Maps

Seismic Base Maps 2013-10-03T13:46:38+10:30

This post is also available in: Spanish

  • Graphically differentiate surveys to find data in areas with long seismic histories
  • Convey shotpoint numbering across diverse survey parameters
  • Upgrade display styles and sampling sequences without complex GIS scripting
  • Show fault intercepts and pick fault polygons on the map view
  • Produce publishing quality posting and ribbon maps of interpreted data
Geoscientists familiar with generic GIS workflows will experience a step change in their expectations of how quickly and effectively they can display rich seismic content in a presentation quality map context.

The 2D and 3D seismic display options enable display of the seismic survey history of an area to allow differentiation of vintage, ownership, processing history and other parameters using established petroleum mapping conventions.

Petrosys seismic base map generation for 2D and 3D survey data can be used throughout the seismic life cycle from survey design through acquisition to interpretation and long term seismic data management.

The Petrosys seismic base mapping tools present a common user interface for mapping data from the many different seismic interpretation tools to which Petrosys connects, automatically adding user authentication and data selection dialogues to take advantage of features unique to individual applications.

2D Seismic Survey Base Maps

A default 2D seismic base map layer is created from the 2D display option by selecting a data source, an optional line selection, and a default style for the lines. The range of seismic line styles supported includes a variety of shotpoint symbols and connector types.

To differentiate surveys using alternate styles the user can either create multiple map layers with different line selections, or apply a line style selection file that selects styles and posting increments based on line naming.

Overposting can be reduced through both automatic annotation suppression and through graphical editing.

Based on many years of experience in posting generations of seismic surveys across all continents, the Petrosys base map tools include a range of controls over shotpoint and line segment interpolation. Petrosys is fully coordinate reference systems aware, so seismic navigation data may be stored as supplied without being compromised by selection of any one specific datum conversion, and can be replayed on maps correctly overlaid with other data using alternate past, present and future coordinate systems.

For the design of 2D surveys a ‘Seismic Line Create’ option on the Petrosys map canvas allows one or more seismic lines to be created graphically and then replicated at a selected offset to create a survey proposal.

Posting 2D Interpretation

Interpreted times, depths or velocity data can be added to a seismic base map through additional control tabs on the 2D seismic map dialogue.

Data can be posted numerically alongside shotpoints with fully control over the interpolation increments, text styles and angles.

Ribbon displays, representing the interpreted data through a color gradient, can be selected as can the contour cut intercepts on which they are based.

Where a data source includes an interpretation of a specific termination type such as a fault top or base, onlap or offlap, these terminations can be represented symbolically to allow visual or interactive estimation of the underlying geological feature on the map view.

A number of additional features are available when data are imported into a Petrosys seismic data file. Line intersections can be computed, and the shotpoint numbers and misties in interpretation values on the intercepting lines can be posted. Seismic velocities can be computed and posted both at regularly interpolated and at stacking velocity locations, providing useful visual information on data quality.

3D Seismic Base Maps

Petrosys recognises a number of spatial forms that describe 3D surveys:

  • 3D bin grids can be managed in the dbMap PPDM database, and also accessed directly from many of the connected seismic workstations. A 3D bin grid includes the definition of the survey geometry, full fold and partial fold outlines, and the definition of any polygonal exclusion areas.
  • 3D survey areas are survey outlines as polygons, computed from various sources.
  • 3D surfaces are collections of 3D survey picks on interpreted horizons, read directly from an interpretation workstation

It is also possible to extract in-lines and cross-lines from a 3D survey and manage them using 2D functionality, which may be necessary when dealing with legacy data management systems.

The display of a seismic 3D bin grid allows control over the annotation styles posting frequency for in-lines and cross-lines, and posting of any information associated with the survey including data extracted from its acquisition and processing history.

Differentiating Seismic By Processing History and Other Attributes

Various attributes associated with seismic lines and surveys can be used to highlight information on base maps for data management projects.

Thematic queries can be used to differentiate the line styles used for 2D seismic line segments based on any information that can be queried on the line. In conjunction with the dbMap assets module, for example, it is possible to create maps showing all seismic lines with the line segments that are loaded to workstations highlighted.

Using line and survey selections, data can be separated into map layers based on ownership status, processing history and other information.

Exporting Seismic Base Maps

Most data rendered on a Petrosys map can be exported to a range of generic spatial formats. This allows 2D and 3D seismic base maps to be sent to GooglEarth via KML, and to a range of GIS products such as ArcGIS via ShapeFiles.

Petrosys harnessing of Oracle/Spatial technology allows selected seismic location data from a dbMap / PPDM database to be queried using Oracle/Spatial SDO queries, and to be published to ArcSDE layers without the need for separate data loading and management procedures.

Standard seismic base maps, including views of interpretation in progress, can be published on a web map services (WMS) server to allow web browser and Esri desktop viewing for sharing information across regions or in large scale data management projects.