Creating Spatial Feature Classes Based on Proximity, Overlay, and Attributes - Introducing Geographic Information Systems with ArcGIS - page 430

1. Start ArcCatalog. Copy the Gold_Data folder from
[___] IGIS-Arc to your
___IGIS-Arc_ YourInitials folder.
2. Make a folder connection to the
___IGIS-Arc_ YourInitials \Gold_Data folder.
The personal geodatabase PGDB_gold.mdb contains a personal geodatabase feature data set named
PGDBFD_gold, which contains the personal geodatabase feature classes Getrich_county, Soils, Oilw, and
Wagt. PGDBFD_gold.mdb also contains a table named soil_type.
3. Carefully look at the geographics and attribute tables of each feature class, so you have a good
idea of what you have to work with. Identify the three named wagon trails. What are they?
________, ________________, ________________ How many oil wells are there? ________ How
many different soils polygons? ________.
4. So that we know precisely where the oil wells are, add the x- and y-coordinates to the attribute
table of Oilw. (If you don't remember how to perform the ADD XY operation, check your Fast
Facts File or the Help files.)
5. Look at the attribute table for Oilw, to be sure POINT_X and POINT_Y fields were added. Start
ArcMap with a blank map. Close ArcCatalog. Add Oilw to the map. Check that the map units
and the display units are set to meters.
The first step in solving this problem will be to make buffers. You will use the Multiple Ring Buffer tool
because the wagon trail specifications require two buffers. The first buffer will be around the oil wells.
Even though we need only one buffer, we will use the Multiple Ring Buffer tool, if only to get used to
using it.
6. Start ArcToolbox. In Analysis Tools > Proximity, launch Multiple Ring Buffer. Check the tool out
again with the Help panel.
7. For Input Features, browse to Oilw in
___IGIS-Arc_ YourInitials \Gold_Data\PGDB_gold.mdb\PGDBFD_gold
and add it. (Or get it from the dropdown menu in Input Features.) Put the Output feature class in
PGDBFD_gold, calling it Oilw_buf. For Distances put in the number of meters that is appropriate
(check the problem statement) and press the + sign. Scroll down and make the Buffer Unit
Meters. For Field Name type OilwNoGold. Press OK. When the tool stops close the window. This
tool automatically adds the result to the map, so the polygons representing the oil well buffers
should appear as a layer in ArcMap. (If not, add the layer.) Examine it.
8. Open the attribute table of Oilw_buf. Notice that the OilwNoGold field has the value 2500 in it.
You will use this when you extract features from the overlay. Since the gold is not within this
buffer, you will want to find those polygons where OilwNoGold is not 2500. Also notice the table
has only one record. Use the Identity tool to click one circle and notice that they all light up.