Answers…But More Questions

NSS/CDS – Thank you!!

Pottery shard

Decompressing on 100% oxygen

Kris helps Bob with a cylinder

Divers Alert Network

Mike and Sandy – proudly hold three empty reels

Day four of the 2006 expedition turned out to be a beautiful day with a slight breeze with birds laughing in the treetops and the team in high spirits. After a good night’s rest and a solid breakfast, the team loaded the tanks and split into two groups in order to effectively accomplish the morning tasks. Cold bebidas (drinks) were deliverd to the workers at the chicken place. The muchachos made quick work of the tanks, with Juan being ribbed a little for being the youngest and Gabriel being ribbed a little for being “machismo.” The muchachos are incredible and a great help. Once we got the tanks sorted and rigged, the teams suited up and headed into the clear cool water.

Mike and Sandy headed back up to the new area carrying two stages for themselves and two stages to set up for Renee and Andy’s push dive tomorrow. We dropped our first stage at the bottom of the rise to The Loft and swam to the second T, dropping the stages for Renee and Andy. We then tied off near the intersection and headed northwest into virgin passage. Michael ran the reel and picked the placement while Sandra followed collecting survey data (depth in feet, azimuths and distances from one survey point, or station, to the next). The passage went east for a while and tied back into our line. We checked another lead off that same new line and again headed east. Mike tied off in going passage when the reel ran low. There was still much to do. On the way back from the new area to The Loft, Mike checked the top of breakdown that headed up and up. He turned after blowing out the passage. Debris dislodged from his exhaust rained down from above and due to the loss of visibility he decided to return to the main line. Returning through The Loft, we tied off just before the drop into the Halocline Room and headed up into a new passage paralleling the Halocline Room. In the floor of this smooth rounded passage were holes through which we could see the passage below and the line running through it. It was a fun passage and has been christened The Rafters. That line also was tied off with passage disappearing east. We dropped through the largest hole into the Halocline Room, picked up our stages and swam up a side passage heading into the Denial Line. We swam up that line, collected a little survey for verification purposes and swam out another line from the same area. Andy and Rhiannon had headed into that area and collected complete survey. It will be very interesting to see how In The Gods relates to the Denial Line and possibly to the Time Line area. We swam out, seeing Andy and Rhiannan on decompression ahead of us. This time we were not visited by the blind catfish while on deco (he stayed with Andy and Rhiannan), however he did swim past as we made our way out after a dive of 199 minutes. Mike emptied two reels, Sandy got thorough survey data and both ended the day as happy campers!

Bob and Renee went back into Cenote Camilo in an attempt to re-verify the continuous stream of conflicting data on the downstream side of the cenote. Today, they were to swim to the Black Forest Line jump (a jump occurs when a diver wishes to “jump” from one line to another that are not connected. This way a continuous guideline to the surface will be maintained at all times to help ensure a safe exit.), survey up the Black Forest Line to the Kilimanjaro Line jump…make the jump and survey out to Blind Cave Fish Line. They hoped to verify map placement of these lines. Bearing 4 bottles each they slowly headed down the dark side of the cenote. It was an easy swim to Carla’s line where they dropped one bottle for their return trip. Shortly afterwards, the cave surprised them again. It appeared there was a jump (indicated by two adjacent line arrows on the line both pointing to the nearest exit). Both Bob and Renee began searching to the left in a big passage area, but couldn’t find anything. Not giving up, we began a search to the right side, even though we weren’t expecting anything there. Bingo, we found a jump. Renee went to investigate and much to her surprise it was marked as Little Cave…the same line that baffled Renee and Bob a few days earlier…only this time it was farther into the cave. Now there are two lines that lead to Little Cave…hmmm. Renee took some tie-in data (data used to verify where the lines intersect) and then they moved on with their mission. They reached the Black Forest line and Renee began taking tie in data at that site, while Bob closed the jump with his gap reel (a reel with less line used for jumps). They then proceeded up the Black Forest line. Similar to yesterday’s dive, the terrain immediately changed into a dark mountainous forest (apply named). Approximately 100 feet in and 20 feet shallower, they found the Kilimanjaro Line. Again Renee took tie in data. Due to the previous time spent at Little Cave, air supply was diminishing, so they turned the dive and headed back. The survey from Kilimanjaro to the Blind Cave Fish Line would have to wait for another day. Renee continued to acquire survey all the way back to the Low Silt Line. They ended the day on deco and a photo session, which helped pass the time. After 130 minutes, they finally surfaced to have their first conversation of the interesting dive!

Andy and Rhiannon went to go off to do some re-survey of part of the upstream section of the cave that has been causing Andy some head-scratching as regards the mapping of the system. They took 4 bottles and spent most of the time at a depth of around 70ft – this was right in the halocline layer. (the interface between the lighter fresh water and the more dense salt water.) As a diver swims through this layer they stir up the surrounding water, creating a blurring effect and providing some ‘interesting’ challenges when reading azimuth data from a compass. The amount of time spent at 70ft depth meant that their decompression obligation was 67 minutes in total – but by virtue of the wonder gas (oxygen) this was safely reduced to a more palatable 21. Once they were back at the accommodation, Andy input the data into a computer mapping program to check their work. They were both relieved to see that the data made more sense, and more closely related their memory of the actual cave.

Kris became part of the assembly line today checking pressures and testing the oxygen level of the gas inside the tanks, along with part of the dive team. They all read 21% oxygen (i.e. plain old air). Following that Kris assisted Andrew with repairs on his primary light, learning the details of the very bright HID (High Intensity Discharge) lights the divers are carrying with them.

Back at Villas DeRosa’s, Bob, Renee and the rest of the dive team returned to fill out their Project Dive Exploration forms. The Akumal mission and its divers are part of this project, sponsored by DAN. Each diver is wearing a small computer attached to their harness (in addition to the two personal dive computers they each wear). The computers are loaded with diver profile data and will be sent to DAN after the mission. They will extract the information from each individual computer and add it to their data banks to help them study diver profiles and ultimately make diving safer for all divers. We are happy to be part of this project and further the education in the diving community. To learn more about this project you can visit their website at

Thanks to the Cave Diving Section for project funding! This contribution will go toward the hire of our muchachos and the purchase of 100% oxygen for use during decompression. The muchachos are wonderful, we really couldn’t accomplish as much without them (and they tote two tanks at a time through the jungle in flip-flops, just incredible!). Watching the change in decompression time from air (21% oxygen) to 100% oxygen makes us grateful for every breath of pure oxygen. Switching to oxygen cuts the time by approximately a third. The Cave Diving Section is a section of the National Speleological Society. Anyone interested in caving or cave diving can contact the CDS online at

Team Members:

Bob Giguere
Andy Pitkin
Michael Poucher
Sandy Poucher
Renee Power
Rhiannon Raggatt
Kris Shannon
Karl Shreeves
Thecia Taylor

Questions and Comments for the Trilobite:

Linda Andzulis

Hello to Renee Power, participant in the Akumal Expedition: Hope
all is well and your expedition is going great!

Linda Andzulis

Hello Linda, All is well here. We are exploring and going places no one has gone before! Thanks for checking in.

Hi Y’all —

It’s so cool that we can see what you’re up to. Thanks for sharing with us.
We’re learning so much through your adventures. . . . but Scorpions &
chicken processing–glad we missed that! Have fun and be safe . . .

The Shannon- Immenhausen Clan

PS – Won’t be long till TJ’s there helping out, until then hooray for

Hey Family gang,

Yes the chicken processing was quite the adventure! The scorpion was just a lucky find.
The muchachos have been a huge help with tanks & with keeping up with what is happening at both cenotes… TJ should be on the trails as soon as he is walking I suspect!
See ya’ll Friday,

Hey Renee
Are you having fun (that’s my question)? Looks like a great time if you’re not afraid of diving. You need to be in more pictures without a bunch of cylinders. Looks like a redneck back yard, just kidding. Anyway that is really great getting to go down there. I know you’ll enjoy it. Have fun. Keep me posted.

Consider yourself posted! You should be down here helping us schlep these tanks. Tell everyone in Little Rock hello and to tune in!

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