This tutorial will show how to interpolate point data to a 3D Grid using simple Inverse Distance Weighting. In this tutorial we will interpolate 1D geophysics, but XYZ points are interpolated in the same way.
For more information about basic interpolation and kriging, please look at this presentation.
You can use any project that contains points data or XYZ points, e.g., the project you created in the Tutorial “Add XYZ Points” or the project you created in the Tutorial “Add Geophysics”.
1. Right click the “TEM 40” node (1D geophysics) in the Object Manager tree and select “Interpolate…” to open the “Interpolation Wizard”.
2. In the “Algorithm” page select the 3D “Inverse Distance Weighting” algorithm.
3. Go to the “Source Data” page. Press the “Get Data” button. Set “Vertical Sample Distance” to 5 and press “OK”
4. Go to the “Settings” page. Check that the “Exponent” is set to 2.
5. Go to the “Search” page. Set “Search Ellipsoid” to 500 for X and Y and set Z to 5.
6. Go to the “Grid Geometry” page. In the “Grid Extent” box press the “Scene Extent” button to set grid size to scene extent. Set “Z Min” to -200, and “Z Max” to 100.
In the “Node Spacing” box set the node spacing to 150 for “X” and “Y” and 5 for “Z”. Press “adjust” to adjust Grid extent according to node spacing.
7. Go to the “Destination” page. Check the “New 3D Grid” radio button. Select a file name for the created 3D grid, e.g., “[path]\MeanRes.grd3”. Enter “MeanRes.grd3” in the “Name For Created 3D Grid Dataset:” box. Enter “MeanRes” in the “Name for Created 3D Grid Object” box.
8. Go to the “Finish” page. The interpolation wizard is ready to interpolate the Tem40 data and the “Finish” page gives a summary of the entered values in the wizard. Press “Finish” to perform the interpolation and to create a new 3D grid object as illustrated in image below.
1. Double click the 3D grid node in the Object Manager tree to open the property dialog for the 3D grid we just created.
2. Go to the “Nodes” tab. In the “Node Points” box un-check the “Visible” check box.
3. Go to the “Slices” tab. In the “Horizontal (XY)” box, press Add and check the “Visible” check box. Press the “Apply” button. You can add as many horizontal slices as you want.
4. In the “Horizontal (XY)” box drag the slider to the right to move the horizontal slice up and the MEANRES grid will appear as in image below.
1. Go to the “Slices” tab. In the “Horizontal (XY)” box un-check the “Visible” check box. Press the “Apply” button.
2. Go to the “Isosurface” tab. Check the “Visible” check box. Set “Increment” to 1. Move the slider to the right to change the isosurface value to approximately 70.
1. Open the GeoScene3D Toolbox from the main window toolbar.
2. Select “Add Files From Source Manager…” from the File menu.
3. Select the file for the 3D grid you just interpolated.
4. Select and right click the 3D grid file in the left portion of the Toolbox window. Select “Grid Value Operations…” in the menu.
5. In the “Grid Value Operations” dialog select the operation “Smooth”
6. Press “Execute”. In the save grid dialog that appears select the grid file you just interpolated. Confirm to overwrite the grid file.
7. Press “Close” to close the “Grid Value Operations” dialog.
8. Close the Toolbox window.
9. Double click the isosurface in the 3D window or the node in the Object Manager to open the 3D Grid property dialog.
10. Press “Refresh Data” to see the smoothed isosurface.