Geosoft Grid Exchange File, an ASCII grid format mainly used for terrain elevation data but also for raster data for concentrations and similar. GXF files are found on the NURE National Uranium Resources USGS data set. GXF format does not provide coordinate system information, so the coordinate system must be manually assigned after importing images from GXF format.
To import from GXF format:
Choose File-Import from the main menu.
In the Import dialog browse to the folder containing data of interest.
Double-click the file ending in .gxf for the data of interest.
A table and an image will be created.
We can double-click on images that are created to view them.
The image appears without using the correct projection. That is a good reason to avoid using GXF format whenever possible, to avoid the tedious work of finding out what coordinate system is supposed to be used and then assigning it.
We use the Style pane to color the image using a palette as seen above.
The display shows uranium concentrations in Alaska.