Cave Diving Mexico - May 2016

Hi all

Just got back from Mexico after 10 days of cave diving out in Mexico, so thought I'd write a little report.

I was actually a diver before I became a caver and have pursued my cave diving "qualifications" by the normal for divers, technical agencies.  This is very different to the mentor type approach used by the CDG. Indeed many of the skills could be deemed rather useless in UK caves, but training is training and most importantly.......the underwater caves in Mexico are beautiful. Like properly stunning. Which combined with super clear water makes them lovely dives.

For those that don't know, there are no surface streams / rivers in the Yucatan peninsula and so all of the freshwater flows underground through the cave systems.  Most of these caves were at one point dry and so are incredibly well decorated, they were then flooded leaving a shallow, clear divers paradise. Although those that prefer mud, tears and hardship in UK caves may disagree!

I've actually been to Mexico a few times and always dive with the same people / shop as they do great courses and have a set up which really makes life easier. I am on holiday remember.

Anyways, I did 3 days of refresher training with a guide as well as some nice pleasure dives in Cenotes Naharon, Aktun Ha and The Pit.  I then did 4 days of training to complete a course I wanted to do, before another couple of days of pleasure diving in a couple of caves; Kalimba and Xulo.  The training contains the same type of things that UK diving does, but obviously tailored for a very different environment; following a line with a blindfold on, managing failed diving regulators etc, taking your mask off and still swimming along.  One thing that doesn't get taught much here is gas sharing with a buddy given that usually people dive solo in the UK. Or are too tight to share.

Ive managed to get a few dives in of late with a few people in the UK including Irn Bru and AH147 from UKC - so thanks guys as it certainly made diving on holidya seem a lot easier and more relaxed especially during the training.

Many of the caves are set up for "tourist" diving so most contain guidelines already and there are surveys available for planning your dives.  There are benches by the entrance pools and you can even get a beer at some of them.

You get a huge variety of dives in Mexico, often distinguished by whether the caves are shallow and therefore freshwater, or deep (for Mexico) and contain saltwater. I am sure some of you have seen pics of when you meet the boundary of the two and you get an amazing, shimmering effect called the halocline.  Naharon is very dark, tannic stained walls and a rather silty floor whilst The Pit and Kalimba are bright white and full of stalactites and stalagmites. The floors in the caves are covered in flakes of calcite I assume from surface rafts when there was less water in the caves and they were still forming.

The final dive of the trip, Xulo, was fantastic. The entrance almost feels like proper caving, well, it's underground and there are bats buzzing you as you kit up in a dark pool.  Underwater there is a real mix of large passages and chambers, combined with lowish beddings with travertine dams and the remnants of crystal filled pools everywhere. Its really nice being able to move 3 dimensionally and float up to have a look at various formations. I was thinking Eldon Hole's main chamber would be much improved if it was underwater the other day. Less climbing involved to go see Damocles etc!

Anyways, it was good and I want to go again. There is a video below of the last dive we did at Xulo for anyone interested. Filmed / Edited by Lelle, one of the guides. WARNING it features pan pipes, you have been warned.

https://www.youtube.com/watch?v=Z4SD...ature=youtu.be

Hopefully over the next few days I will be getting out again in the UK.  My last dive before this trip was in KMC, and I am hoping to go to Didos at some point. Should be a nice contrast.

Matt
 

chunky

Well-known member
Great report. Thanks for sharing.

Can't follow the link on the phone but will check it out later.

Sent from my SM-G928F using Tapatalk
 

Pitlamp

Well-known member
Really enjoyed watching that Matt. I can see why some outside agencies teach finning techniques which aren't generally necessary for cave diving in the UK.

As you may know I have an interest in stals in water filled caves. In several places on the video (notably at 0.57 and around 6.32) there are stals which appear to have been broken but then show some regrowth.

My understanding is that those low lying caves were exposed to air when sea levels fell during the previous ice age, allowing stal growth. Then the caves became resubmerged as the earth warmed up and sea levels rose due to melting ice - that right?

If so, any broken stals with regrowth must have been damaged before the last glaciation, allowing regrowth before the sea level rose. Or do water levels fluctuate with the weather in modern times, allowing regrowth following accidental damage by divers? Any thoughts?
 
Pitlamp

Personally, I doubt that water levels fluctuate enough and over enough time to allow regrowth in modern times. Diving in Mexico is a relatively new thing (I think 1980s was the first thrust of exploration) so there is no way you should be able to see visible regrowth after diver damage.

Given that there is evidence of human presence in these caves, they were obviously dry at some point for a reasonable period.  Maybe they were damaged by wind / flooding cycles / animals and then regrew.

Something else which is quite complicated is that in most places the caves are shallow, but in maybe 3 or 4 places the depths approach 100m (El Pit, Hoyo Negro, Blue Abyss and A.N. Other). In all of these except the last there are no formations below 50m. You could therefore postulate that the water levels never dropped below that. But.. in the last site as documented in another video I will send the link of to you, there are formations (and large ones) way below this towards 90m - meaning a much greater drop in water level.  Which means, either a localised variation in water depth changes (odd given how interconnected everything is) or massively different ages of cave passage.

Matt
 

Pitlamp

Well-known member
Very interesting, thanks. I remember one of Rob Palmer's Blue Holes expeditions sampling stal at about -90 m, I think.

The problem is that sea levels have fluctuated frequently - and by varying amounts - throughout the last million years (due to several glaciations) so the maximum depth to which different caves have been drained depends on their ages.

You should do more video work; it's good to watch.
 
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