The Crystal Cave – Naica, Mexico with Dr David Rosengren
It was hard to knock back the opportunity to join 60 Minutes Australia for a trip into The Crystal Cave in northern Mexico. After 2 years of (no doubt costly) negotiation, producer Danny Keens was given permission to take a crew into the the tightly guarded cave located a mile beneath the surface within the Penola lead mine in the desert mountains of Naica in northern Mexico.
Discovered in 2000 by two brothers doing mine blasting, the cave has formed along a volcanic fault line where, filled with volcanic heated water in a closed environment for centuries, gypsom minerals have consolidated to produce massive selenite crystaline structures at a scale up to 10 times greater than previously discovered.
Along with TV journalist Michael Usher and crew (cameraman Andy Taylor and soundman Chick Davies), I was invited along to provide medical support. We were joined by world renown UK volcanologist Dougal Jerram to complete the team.
Why was medical support needed? The environment necessary to produce such an awesome display of nature is such that human life cannot survive for any prolonged period. With a minimum temperature of 45 deg C and an average humidity of 100%, the bodies ability to lose heat is immediately overcome.
Any ability to lose heat through evaporation, conduction, convection and radiation are overwhelmed.
From the moment you step into the cave you begin to cook as the body temperature attempts to equilibrate with the environment.
My research prior to arriving (and there was very little to help) suggested that at best we could safely stay inside the cafe for 10 minutes at the most. This proved to be completely correct. There are no words to describe the overwhelming assault on the body senses as you step into the cave. It is easier to describe the sense of overwhelming panic to get out that begins to develop after about 10 minutes inside.
So what strategies did I employ to keep us safe?
- 2 pedestal fans purchased from a hardware store in Chihuahua and plugged into a power source in the mine ramp outside the cave entrance
- A handful of cheap plastic pump spray bottles
- 2 eskies with chilled bottled water – restocked with ice by mine security staff
- strict time keeping to ensure that exit from the cave was enforced after 10 minutes
- Approx 1 hour rest time in the cooler (35 deg C) and less humid (75% humidity) environment of the mine tunnel adjacent to the cave
Spraying cool water over our face and neck using simple pump spray bottles and sitting in front of a cheap pedestal fan to support evaporative cooling was a very efficient method of cooling.
Using hand held electronic Welsh Allen thermometers I monitored the oral temperature of all members of the team both within the cave and also during recovery periods outside. Within 10 minutes the temperature in all was above 39.5 and in some reached above 40 deg C.
It was hard to achieve much with such a short time frame so we trialled some cooling suits to see if we could prolong trips inside the cave. With a small backpack full of ice and water and a small battery operated pump to circulate the iced water through tubing sewn into the shirt and pants, we were able to stretch our time inside the cave out to 20 minutes.
The crystals are extraordinary. The raw size and beauty of the cave assaults the senses in much the same way as the oppressive conditions. It is not until we had been into the cave multiple times that we were able to control our senses and emotions to really appreciate the extraordinary opportunity we had been given.
There are very few places on the planet that are not accessible to the general population and this is one of those such places. I am extraordinarily grateful to have been given the opportunity. To get everyone out safe and sound was an added bonus.