Changes

====Baselap====

====Baselap====

Baselap can be achieved in several ways. To baselap one grid onto another for the purpose of cross section display and volumetrics work, the elevation ''z'' values at each grid node are compared and the maximum value is retained in a new grid. This makes the two grids coincident in the area where the upper grid is missing due to base lap ([[:file:using-and-improving-surface-models-built-by-computer_fig9.png|Figure 9]]).

Baselap can be achieved in several ways. To baselap one grid onto another for the purpose of [[cross section]] display and volumetrics work, the elevation ''z'' values at each grid node are compared and the maximum value is retained in a new grid. This makes the two grids coincident in the area where the upper grid is missing due to base lap ([[:file:using-and-improving-surface-models-built-by-computer_fig9.png|Figure 9]]).

Contour maps of baselapping surfaces should have no contours in areas of baselap because the surface does not exist there. To baselap one grid onto another for map display, the elevation z values at each grid node are compared and the value of the baselapping grid is set to missing if lower or kept if higher than the other grid ([[:file:using-and-improving-surface-models-built-by-computer_fig9.png|Figure 9]]).

Contour maps of baselapping surfaces should have no contours in areas of baselap because the surface does not exist there. To baselap one grid onto another for map display, the elevation z values at each grid node are compared and the value of the baselapping grid is set to missing if lower or kept if higher than the other grid ([[:file:using-and-improving-surface-models-built-by-computer_fig9.png|Figure 9]]).