I was playing with my friend, and they claimed that proximity mines counted as an obstacle, so they could use seismic charges to blow up their own proximity mines, and hit my ships with the effect of seismic charges. That just doesn't seem right, but I allowed it for that game and came here to try and find out. As far as I know, any dropped bombs and mines are separate from obstacles, right? I thought that only asteroids, debris clouds, gas clouds, and electro-chaff clouds could be destroyed by seismic charges. If I'm wrong, are there any other interactions that I might be missing?