This plugin, for the open source seismic interpretation platform OpendTect Version 6.4.0 or later, creates a 3D horizon/grid from the 2D and 3D horizon interpretation in an OpendTect survey/project.

Description

The plugin adds a "Grid 2D-3D Horizon..." item to the "Processing|Create Horizon Output" menu which opens a dialog box for:

  • Selecting 2D and 3D seismic interpretation to grid
  • Specifying the output horizon name, extent and inline /crossline interval
  • Specifying a cropping polygon
  • Specifying a set of fault polygon constraints
  • Selecting the interpolation algorithm to use

In the current release the plugin includes two gridding/interolation algorithms:

If fault constraints are provided only input data on the same side of the fault is used to interpolate a grid node.


Example of continuous curvature spline gridding without fault constraints
Example of continuous curvature spline gridding without fault constraints


Example of continuous curvature spline gridding with fault constraints
Example of continuous curvature spline gridding with fault constraints


Example of inverse distance squared gridding with fault constraints
Example of inverse distance squared gridding with fault constraints

Input Parameters


Grid 2D-3D horizon plugin input data selection dialog
Grid 2D-3D horizon plugin input data selection dialog


Grid 2D-3D horizon plugin input dialog, showing Bounding Box grid extent and continuous curvature interpolation settings
Grid 2D-3D horizon plugin input dialog, showing Bounding Box grid extent and continuous curvature interpolation settings

  • Grid Extent: Two options available:
    • Bounding Box - set the output horizon extent from the extent of the input data, adjusted to snap to the specified Inl/Crl steps
    • Horizon - set the output horizon extent to match an existing horizon in the survey/project
  • Inl/Crl Step - Under the BoundingBox Grid Extent option the output grid spacing can be specified relative to the 3D survey step/sampling
  • Cropping Polygon - select a polygon to crop the grid output
  • Fault Polygons - select polygons to use as fault constraints during gridding. Suggest fault naming scheme that prefixes the polygons with "f_horizon name" to make them easy to select
  • Algorithm - Local Continuous Curvature Tension Spline parameters:
    • Search radius - only data within a square +/- this radius is used to estimate a grid node
    • Tension - the spline tensioning parameter, varies from 0 (equivalent to Minimum Curvature) to 1 (equivalent to an elastic membrane)

Grid 2D-3D horizon plugin input dialog, showing Horizon grid extent settings and inverse distance squared interpolation settings
Grid 2D-3D horizon plugin input dialog, showing Horizon grid extent settings and inverse distance squared interpolation settings

  • Algorithm - Inverse Distance Squared parameters:
    • Search radius (if checked) - only data within a square +/- this radius is used to estimate a grid node, otherwise use all input data (subject to the fault constaints) for each grid node.