Changes

==Autopicking==

==Autopicking==

[[file:interpreting-3-d-seismic-data_fig13-5.png|thumb|{{figure number|1}}. &copy; Dorn.<ref name=Dorn_1998>Dorn, G. A., 1998, Modern 3-D seismic interpretation: The Leading Edge, v. 17, no. 9, p. 1262-1272.</ref> Courtesy SEG.]]

[[file:interpreting-3-d-seismic-data_fig13-5.png|thumb|{{figure number|1}} &copy; Dorn.<ref name=Dorn_1998>Dorn, G. A., 1998, Modern 3-D seismic interpretation: The Leading Edge, v. 17, no. 9, p. 1262-1272.</ref> Courtesy SEG.]]

Autopicking (or autotracking) has been around in interactive interpretation systems since the early 1980s. The concept behind autopicking is quite simple. The interpreter places seed picks on lines and/or cross-lines in the 3-D survey. These seed points are then used as initial control for the autopicking operation. The algorithm looks for a similar feature on a neighboring trace. If it finds such a feature within specified constraints, it picks that trace and moves on to the next trace. Simple autopickers allow the user to specify a feature to be tracked, an allowable amplitude range, and a dip window in which to search.

Autopicking (or autotracking) has been around in interactive interpretation systems since the early 1980s. The concept behind autopicking is quite simple. The interpreter places seed picks on lines and/or cross-lines in the 3-D survey. These seed points are then used as initial control for the autopicking operation. The algorithm looks for a similar feature on a neighboring trace. If it finds such a feature within specified constraints, it picks that trace and moves on to the next trace. Simple autopickers allow the user to specify a feature to be tracked, an allowable amplitude range, and a dip window in which to search.

==Voxel tracking assumptions==

==Voxel tracking assumptions==

[[file:interpreting-3-d-seismic-data_fig13-6.png|thumb|{{figure number|2}}. Copyright: Dorn, 1998; courtesy SEG.]]

[[file:interpreting-3-d-seismic-data_fig13-6.png|thumb|{{figure number|2}} &copy; Dorn.<ref name=Dorn_1998< /> Courtesy SEG.]]

[[:file:interpreting-3-d-seismic-data_fig13-6.png|Figure 2]] is a sketch of a simple voxel tracking algorithm and its behavior under two different continuity constraints. Six-way connectivity restricts the search from one voxel to only the neighboring voxels that are connected face to face. Twenty-six-way connectivity allows the search to proceed between neighboring voxels that are connected face to face, edge to edge, or corner to corner. The connectivity constraint that is used affects the outcome of the voxel tracking.

[[:file:interpreting-3-d-seismic-data_fig13-6.png|Figure 2]] is a sketch of a simple voxel tracking algorithm and its behavior under two different continuity constraints. Six-way connectivity restricts the search from one voxel to only the neighboring voxels that are connected face to face. Twenty-six-way connectivity allows the search to proceed between neighboring voxels that are connected face to face, edge to edge, or corner to corner. The connectivity constraint that is used affects the outcome of the voxel tracking.