ArcExplorer Java Edition for Education (AEJEE), ESRI's free, downloadable, dual platform (Win/MacOSX), lightweight GIS tool, comes with a series of built-in projects that allow users to explore a number of interesting topics. One of the projects is "worldtectonic_hd.axl", which looks at earthquakes and volcanoes around the world.

The earthquake data set is 57,600 points over a five-year period. If you do a query on this many points, on some computers, it just takes a little too long to respond. Here's a little trick that can make your life easier: slim down the number of points. You get almost the exact same pattern (and learning) with one year of points. By using just the most recent year -- 2005 -- you can reduce the over 57,000 to about 15,500. It's easy to do.

Load the project and create a query about "qks20012005gt4" (quakes from 2001-2005 that are greater than magnitude 4). Ask to find all those from 2005 by setting the query to be "(YEARMODA > 20041231)"
(Say "Yes" when it asks if you want to see all values, in the query and in the results.) The results will be 15,536 selected. Notice that the data table includes latitude and longitude. This is good news! By clicking the "Save" (floppy disk) icon, you can save the file as a "comma separated values" file. Save it in the \ESRI\AEJEE\DATA\WORLD folder as "qks2005gt4.csv". Then you can import it, by following the process outlines in the AEJEE Tutorial Lesson 4.

Once you have completed the change, delete the old version from the project, set the symbology, and save the project as "worldtectonic2_hd.axl".

((Thanks for the great idea, Martin!!))

- Charlie Fitzpatrick, ESRI Education Manager