OpendTect v6.6 is a project-oriented seismic interpretation system. Projects are organized in Surveys - geographic areas with a defined grid that links X,Y coordinates to inline, crossline positions. 3D seismic volumes must lie within the defined survey boundaries. 2D lines and wells are allowed to stick outside the survey box. It is possible to load multiple 3D volumes with different orientations, bin-sizes and temporal sampling rates into one survey. Volumes that do not match the defined inline, crossline survey grid parameters are rotated and re-sampled onto the grid.