EVS Geology File Creation in ArcGIS

Note: If you are not a licensed user, you may build data files, but you will not be able to utilize them in EVS or MVS because the files you create will not be password protected (allowing them to be used in a demo version). Instead, we recommend that you review Loading Existing EVS Geology or Chemistry Files.

CREATING A GEOLOGY FILE:

The following section will show you how to build an EVS geology file (.geo) with ArcGIS . To see the format for a GEO file click here: $image\shortcut.jpg$ Geology File Format

Click on the "Create EVS Data File" button to reveal:

$image\create_button.jpg$

Choose Create Geology File and this initial window will open:

$image\geo_initial.jpg$

From this menu, you select the layers and features from which you want to extract chemistry data. You can also choose whether to include all features of a layer or only the selected features. Let’s accept the current setting of the borings layer and all features. Hit Next to proceed and the following window will appear.

$image\geo_gis.jpg$

At this point, you specify the fields of your data source that will be used to create your geology file. If your fields are named reasonably, the process of specifying the fields can be very simple because the extension does so much for you automatically. In the example above, the fields of our data source that correspond to x and y coordinates by default are assigned to the x & y coordinates of the points in the shapefile. However, if you wish to use x and/or y coordinates (or Northings or Eastings) from the associated tables, you may do so.

The remaining fields will be automatically filled in according to some rather straightforward rules. In the discussion of these rules, all field names are case insensitive and an asterisk "*" refers to one or more wildcard characters.

Top Surface (used to designate the ground surface) will use the LAST field with any of the following names: "top*", "ground*", or "grnd*".

Boring ID: will use the LAST field with any of the following names: "bor*" or "well*".

Symbols will use "sym*".

Finally, the "Surface(s) Below Top Surface" will automatically select all remaining fields except that all of the following names will be ignored: "id*", "objectid*", "oid*", "fid*", "key*", "pr*key", "<Measure from Point>", "bot*", "X*", "east*", "Y*", and "north*".

Just because a field is automatically selected (or not selected) does not imply that you cannot change these choices. You should always review the automatic selections to see that they make sense for your project. However, the wizard will usually save a great deal of time and if you choose your field names (e.g. field naming during the creation of queries).

In this example our Boring_ID is "Bore", the Top Surface is Top, Z Coordinates are Z and they represent true elevations (as opposed to depths below ground surface).

The wizard has automatically selected Bot1 through Bot5.

BE SURE TO SELECT "Sample Z Coordinates are Depth Below Ground Surface", because that is what the data in our table represents. You cannot rely on the wizard to know if your data represents depths or elevations. If you're not sure, open the table in ArcGIS and have a look! To open the table, choose the "Source" tab and right click on the Geology table and choose open. The table for our example is:

$image\gis_geo.jpg$

Looking at this table, it is obvious that our data is depths. Note that all of the Bot fields have positive values and their magnitude is greater than the Top_ field. If their values were elevations, they would be above the ground surface. This is clearly not possible. However, it is certainly possible for the situation to be ambiguous without having additional information about the site. For this reason, the wizard does not attempt to make this selection automatically.

$image\geo_gis2.jpg$

When you hit Finish, the file browser will appear. Save the file in the ctech\data\geology folder as evs-test.geo:

$image\geo_file1.jpg$

If you have only created or specified a .geo file, when you start the Preview and Launch window you will only be shown applications that utilize geology files ONLY.