[oldvike]

What’s a bounce?

[FReepaholic]

...What’s a bounce?...

It's my understanding bounces are caused by compression in the mountain.

Causes floors, ceilings and walls to crumble.

I'm told bounces are commonplace.

[glock rocks]

A bounce is the same as a bump.

The original bounce that trapped the miners was the walls giving way explosivly inward. The roof held.

[FReepaholic]

I found this:

The Dictionary of Mining, Mineral and Related Terms defines a bounce: a. a sudden spalling off of the sides of ribs and pillars due to excess pressure; a bump.