Tied To The Master Grid

Messing with grids today.  Pretty interesting.  Just remembering how to create grids in SMT and view them in Surfer. Let's get going as to what SMT thinks grids are all about. They know more about it than me. Well, what is a grid? A grid is a rectangular mesh that has interpolated values in them. Two types:

Data Adaptive:  data is outputted to specific locations from a weighted combo of predefined values.

• Flex Grid - Usually the FlexGrid is used because of its fast and give you pretty much what you're after.
• Gradient Projection - The Gradient Projection is best if you're making 3D horizon maps.
• Inverse Distance to a Power - Use the Inverse Distance to a Power when you have sparce values (velocity data, 2d horizons). Cannot estimate highs and lows between locations.

Mathematical Model:  does not used specified values.  Fits a mathematical surface to the data and then interpolated the values.  Give you smooth values and look great.  Looks are not always good.  You have to represent what the underground looks like.

• Cubic Spline - Good when areas are over or under shot.  You can't do faulting.

The cell size is the most important part of gridding.  It's all about interpolating.  Once you go a few cell points outside the data, the software's guessing.  You don't want that.  Find other regional trends in those missing areas.