Bubble-induced cave collapse.

Conventional wisdom among cave divers is that submerged caves in aquifers, such as in Florida or the Yucatan, are unstable due to their ever-growing size from limestone dissolution in water. Cave divers occasionally noted partial cave collapses occurring while they were in the cave, attributing this to their unintentional (and frowned upon) physical contact with the cave walls or the aforementioned "natural" instability of the cave. Here, we suggest that these cave collapses do not necessarily result from cave instability or contacts with walls, but rather from divers bubbles rising to the ceiling and reducing the buoyancy acting on isolated ceiling rocks.

Forensic fluid dynamics and the Indian Spring (1991) cave collapse problem.

Nof and Paldor (Safety Sci 2010;48:607-14) suggested that resonance in the air pockets in the Indian Spring cavern might have contributed to the 1991 collapse. Here, we extend the resonance theory to one pocket in the cavern and a very broad basin that serves as the other branch of the U-tube. Our methodology is to apply familiar fluid dynamics principles to the situation that occurred in the cave.