Chasing Leads and Laying Line

Out and about early today we were. We departed Villas DeRosa at 7:30 AM and headed for the internet cafe. Once the work was done there we were off to Don Raphael’s ranch. He greeted us as warmly as always and we gave him a smaller map of the system as promised. Today was the humidity fest in the jungle. It seemed much hotter and the tanks seemed much heavier due to the changing weather conditions.

Good diving today! Terrence and Andrew clipped on four cylinders and pushed up the Grand Canyon line to the north. The Grand Canyon passage is well named: it looks like a miniature version of the real thing with sheer rock faces containing different-colored rock strata and numerous stalagmites that look like the buttes seen in the Grand Canyon in Arizona. No one in this year’s expedition has been in this passage since it was originally explored in 2000. After sorting out some confusing leads and markings, they found at least three promising leads to the north which they plan to look at tomorrow. They were excited because there may be some unexplored ongoing passage there. Near the end of the line they found some gelatinous sediment that is almost certainly bacteria and a fossilized conch shell that has been exposed by dissolution of the limestone. It is probably several million years old. They also saw several blind Mexican cavefish and the usual (for this cave) assortment of stygobitic (obligate aquatic cave-dwelling) amphipods, isopods and crayfish. Andrew and Terrence even saw a blind cave fish at the very end of the Grand Canyon line. On the way out, they removed a superfluous line near the Muchachos entrance (the one they put in yesterday trying to connect to Cenote Mud), reaching the surface after nearly three hours underwater.

Meanwhile, Renee and Karl headed down the Low Silt Line to check out areas that no one has been in for several years. This area of passage appears more like a Florida cave than a Mexican cave. It has few decorations compared to other parts of the cave, and a limestone structure that’s very dark and sharper than other sections of the system. The divers skimmed the surface of the halocline (where the salt and fresh water interface). Structures beneath the halocline were white due to the salt water encouraging more aggressive cave formation, and they saw very little life in this passage. Both noticed a distinct flow while swimming into the passage. They were close to turn pressure (the point at which they’ve used the maximum allowable amount of air before they have to head back) when they found a promising lead to the west. They put in about 220 feet of line headed westward, toward the upstream section of the cave. They named this new line the Time Line because a) it’s about time someone on this expedition put some line in the cave, b) they were almost out of time when they found the lead and c) Karl lost his brand new G-Shock watch (adding to the two Z-knives he’s already lost on this expedition). On the way out they put some identifying marks on the Cindy Side Passage, finally surfacing after 158 minutes. Depending upon circumstances and expedition priorities, they hope to return there tomorrow to pick up where they left off.

Once back at Villas DeRosa’s the team ate lunch and prepared for the next day’s diving activities. These tasks include filling, analyzing and rigging tanks, preparing survey slates, compiling survey data, logging dives and preparing the daily update.

Thank you to Allison Tysall’s class of third graders Lake Gem Elementary in Orlando, Florida for all of the questions submitted yesterday for the update. The team truly enjoyed answering all of them.

All of us with the Cambrian Foundation need to take the time to thank Conrad Pfeifer at Ocean Odyssey Dive Center in Pennsylvania who has been a long time sponsor. Ocean Odyssey Dive Center has always been eager and willing to support the Cambrian Foundation. For this expedition many of our regulators were purchased or serviced with the help of Conrad and the great team at the dive center.

Team Members

• Andrew Pitkin
• Renee Power
• Karl Shreeves
• Thecia Taylor
• Terrence Tysall
• Yoda

Send Questions or Comments to the Trilobite

Hi again…..have a good dive tomorrow! Hope you find some good leads, especially if you make it to Shawn’s Room!

Thanks, sweetie. From the update, you can see we did find one, by coincidence not too far from the room named for you. Guess your luck is with us! Love you, Karl

Karl Shreeves – Enjoying updates! Especially debate over Karl’s brain size and oxygen consumption. I think something is leaking. I’m curious to know the required depth for decompression and what impact cave distance from the surface plays on decompression? Thanks and be careful Karl.
Been praying for you and the team – God bless – Bob.

Hi, Bob and thanks for your prayers. It means a lot to all of us. Basically, the depth and time dictate decompression requirements. The deeper you go, the less time you have before you require decompression. For example, at 100 feet you have about 20 minutes before you need to make decompression stops (other than those we make for safety), but at 60 feet you have just shy of an hour. Our dives in Camillo tend to be in the 50 to 70 foot range, which isn’t that deep. What leads to long decompression requirement is the long dive times, which are 90 minutes and longer. On today’s, we had more than 45 minutes of decompression required, assuming we only breathed air while decompressing. We cut that down, however, by breathing pure oxygen for awhile. Oxygen removes dissolved nitrogen more effectively, so it shortens the hang time (as we call it).

Hello, Team,

Been keeping up with your excursions and it sounds amazing. Wish you had more photos posted. No underwater cameras? Or perhaps they can go only so deep? Renee, we are rooting for you here in Tennessee.

David and Sandra Hamilton

Thanks David and Sandra! At this time, our update program allows a limited amount of photos. I’d love to post more underwater photos and that is scheduled into the expedition. Typically a dedicated dive is conducted due to the logistics of lighting, etc. Powerful strobes are used in the caves due to the lack of natural light in the cave. Underwater cameras and camera housings (for standard cameras) are rated for different depths. If used beyond their depth rating they are more likely to leak and the functionality of the camera may be reduced by compression of the housing. Certainly an expensive risk! I’m so glad you guys are following along! Next week the students and science team join us so please stay tuned. I’ll have some stories for you upon return. Take care and God bless.
Renee