The cave resonator and the Parker Turner cave collapse problem

摘要

The Parker Turner cave diving accident was unique. Out of several hundred cave diving fatalities that occurred in Florida during the past 50 years, it is the only one that occurred due to a partial collapse of the cave. Here, we propose a natural physical process that might explain this unique accident. While it is possible that the presence of the divers in the cave while the cave collapsed just happened to occur simultaneously, this is unlikely. It is suggested here that resonance in the air pockets in the cavern (or cave), created by breathing (open circuit) divers, may have contributed to the collapse. We propose that divers present in the cavern during the dive may have (unknowingly) caused the collapse through the pressurized air that they release with each breath. When the breathing period of the diver(s) matches the natural oscillations period of our new "cave oscillator", the ensuing resonance causes the air pressure in the pockets to increase uncontrollably. We model the system as a non-uniform U-tube filled with water on the bottom and compressed air on top. The top of the tube is sealed on both sides so that the compressed air is trapped in the chambers above the water. The bottom part of the tube represents the water filled cavern (or cave) whereas the vertical tubes represent the air cavities. We show analytically that such a system is subject to natural oscillations with a period of roughly the same as the breathing rate of the typical diver.