There are more and more shards appearing near my cities. At first I thought it was due to adventure techs, but as I have not researched any of those for some time, and there are now about 7 shards near my cities - two right next to each other- where there was none in the beginning, I'm quite sure now that this is a bug.

Has this happened to anyone else?

I don't know what the trigger is, I alway notice the new shards after loading a game, but as the previous autosave has them already, thats probably not the trigger (or seriously screwed up )