How would a wave (earthquake?) caused by an explosive travel through soil/rock?

I wonder how the shock wave would travel through, say slate rock, both in terms of frequency and intensity. I can only imagine the intensity to dampen with r^2, since it'll be travelling in all directions. Is this a correct assumption?

The frequency something I can only imagine as sort of a lightning impulse kind of thing, with the rise and drop time of the impulse wave.

Does anyone here know about this? My concern is regarding damage to nearby structures.