Is there any point putting a geosurvey team on a civilian mining colony?
If you are buying the mineral output, then yes definately, the might increase the amount of something you need, and (less likely) may increase avalaibilty (which would be a real plus as you get more minerals for the same cash outlay.
If you're taxing the CMC then its less helpful, but still good (it will usually extend the life of the tax base).
and in both cases the team will go up 5% every time it finds something.
best use IMHO is still on your own mining sites, and preferably planets as you are more likely to make a find on a planet than a smaller body.