Correct Instance of Using GeoURL

I'd like to help my si开发者_Python百科te's SEO as much as I can. We have a very large site that is based in San Fran, CA, but covers topics all over USA and Europe. If we put our GeoURL as SF, CA, will this hurt our SEO - making Google thinking all of the content is SF, CA related? Or does that not matter?

This doesn't really seem like a SO question, but anyway: One think you could do would be to tag tages as they apply to geographies. So a page about Paris, France will be tagged there, etc.