Know about geospatial analysis?

I'm building a story involving Jupiter's moon, Io. There's a geological map of it on the bottom half of this image. What I'd like to figure out is which sites have the widest variety of terrain types within the shortest distances? Or, put another way, which sites would be most worth dropping an automated factory down on, as they'd require the minimal amount of road-building to get to a useful variety of resources? Or, put a third way, what's the fewest number of sites that would be required to have a complete set of the terrain-types within, say, a hundred kilometres of each site?

I can sort of see how a computer program might run some colour-detection on that image to figure out a map, and then run some algorithms about the value of each pixel - but that's a notch or two above my programming skill, and I don't think I have the time to both improve my programming skill and keep working on the story.

Any suggestions?

Thank you for your time.