[OpendTect_Users] Importing sparsely sampled horizon

[Marc Langlois]

I am trying to import into opendtect sparsely sampled 3D data points as a horizon for QC purposes. The input data points are in a column-oriented text file with X, Y and time values. The Z values are in this case residual source and receiver statics, but I'd also like to use any other value, e.g. weathering statics, surface topography (converted to time), etc. 

I can import the text file and create a horizon but I can't get the "Grid" algorithm to create a new gridded (interpolated) horizon. Is this possible in OD? If so, what is the recommended procedure and gridding parameters to create a horizon from sparsely sampled points?

The static values are in the range -40 to + 40 ms. Do the negative values cause problems when the survey Z range is from 0 - 6000 ms?
  
Regards,
Marc Langlois

TBI, Calgary, Canada.