Introducing Geographic Information Systems with ArcGIS: A Workbook Approach to Learning GIS, 3rd Edition

Creating DEM files with Kriging

Assume now that you show the results to the archeologist. She is suitably impressed but she is really used to contour lines and would like to see an elevation map in that form. Not a problem.

There are many ways to obtain three-dimensional surfaces from a discrete set of zero-dimensional points. None is exactly right (recall, there is no “exactly” with GIS points, lines, and surfaces, nor is there any “exactly” in any real-world coordinate set), but we can get “close.” We will use the mathematical method called Kriging that you met before to create a digital elevation model (DEM, composed of square elevation posts). We will then use the DEM to make contour lines. If you are faced with a real-world problem of this sort, you may not want to do it this way (or you may), but the main idea here is for you to learn by being exposed to several methods.

____ 40. Start a new map in ArcMap, without saving the changes. From

___ IGIS-Arc_YourInitials\Elevation_Data\The_Dig

add as data the table Mt_P.txt. Open the table to be sure you have a 180-record table, with headings of Point, Northing, Easting, X, Y, H, and Elev_MSL. Close the table.

____ 41. Using Search find the Kriging (3D Analyst) tool in ArcToolbox. Where is the tool? ____________________________________ Double-click the tool name to start the tool.

____ 42. In the Kriging window, for Input point features, browse to

___ IGIS-Arc_YourInitials\Elevation_Data\The_Dig

and click OK. (You may be ...