Last week at the office I experienced the sound of blasting, the way the ground rumbles as the shock wave travels underground.
Now, they're building a Helmart or something down the road, so the weeks prior, you would always hear a blast siren go off before the rumble.
But last week there were no sirens, the rumbles happened at seemingly regular intervals, perhaps 20 seconds apart, ten in a row. Later on when I went our for a smoke break they started up again, same deal.
I noticed the sound was slightly different, as if it was only transferred through the ground and there was no faint blast sound that usually accompanies the blasts from the weeks prior.
It could have been blasting far away, since the whole area is on a large rock shelf as part of the Canadian Shield (le bouclier canadien).
I dunno, I instantly had an ominous feeling, which betrayed my usual (overly) rational self.