When contouring 3D grid data, there are additional options available in the Contour Options dialog. These options let you chose the data that you want contoured. The default array used to fill cells is the active data set. Another option for filling cells is the data colors option; this uses an input array from MODFLOW, MODPATH, MT3DMS, SEAM3D, or RT3D. Any of the input arrays from the models such as Kh, Kv, Recharge, etc. can be displayed, for any stress period. For MT3DMS/RT3D/SEAM3D, you can also specify the species.
GMS interpolates data from the cell centers (for cell-centered grids) to the cell corners and midsides so that the grid can be triangulated and contoured. By default, GMS uses a fast algorithm for interpolating the data that is adequate for the majority of situations. If the Auto-interpolate contours option is turned off, however, you can specify your own interpolation scheme. By default, GMS truncates the interpolated values to the max and min of the data, but you can turn that option off.
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Contours