Jamaican Caving Notes
Minocal's Glory Hole
May 18, 2005
Team: Stewart, Conolley, Slack, Hyde, John, Lee, JIS.
Notes: RS Stewart
This would be a rather unique day, at least for the second session of the JCO contribution to the Parks in Peril Project. We would have a video crew from the Jamaica Information Service (JIS) in attendance. We'd been informed, early the week before, that TNC-J would like us to have the JIS along for a day, and because our schedule was very tight, and difficult to change, this meant that they would be with us for either River Maiden and Falling Cave, both very hydrologically active, or for Minocal's Glory Hole, a very deep cave north of Quick Step. Our considerations were thus: If we took them into one of the river caves, they would be swimming and it was hard to imagine how an inexperienced speleo video crew would manage this without destroying the camera. If we took them down Minocal's, we would have to teach them vertical rope techniques, but if we were in charge of the camera for the actual descent and ascent, we stood a good chance of pulling it off. We opted for Minocal's.
The deep shaft that we would tackle this day was the one pit that we had included in the project. Most had been excluded because there is no actual dark zone, and therefore no chance of trog species. We knew from experience that Minocal's has crabs in its lower sections, and dark zone, so it seemed circumspect to include it. We also had hopes of pushing it further, despite it being rainy-season. The day decided in our original nominal schedule was Wed, May 18, and video crew, or no video crew, we would go down into this sinkhole on this day.
Dr David Lee, and Adam Hyde, had pulled in the previous evening, and so the morning saw five of us dragging our stiff bodies off the concrete floor on which we'd slept, and searching out tea and coffee from Joanne. Breakfast soon followed, and not long after, Kimberly John of TNC-J arrived, running earlier than the hoped-for 9:00 AM. She'd managed this despite a very long drive across a substantial portion of the island.
Because of bizarrely incorrect directions that were given to the videographers on how to get to get to Quick Step (they were under the impression it was near Clarks Town, on the other side of the Cockpit Country), we learned by our intended departure time for the bush (nine in the morning) that they would not reach us until afternoon. As cell-phone calls were exchanged with the JIS crew, which repeatedly cut out, we contemplated our options. Eventually, it was decided that part of the current team would proceed to the hole to begin setting things up, and the others would await JIS in Quick Step. Ivor drove the advance crew up to the start of the hike to the hole, leaving Kimberly to watch for JIS, and then he returned to Quick Step to rejoin Kimberly so that JIS, when they arrived, would be sure to find us.
We'd picked up a local helper somehow, who when we reached the start of the hike to Minocal's Glory Hole put on a very impressive display of machete work as he forged down into the cockpit that held our target. We followed, and steered him through the bush until the large, impressive entrance shaft is reached. This well-groomed track would prove to be a great help on our departure from the shaft later in the day. Gear and ropes were then moved to the entrance, and we began the task of rigging the pit. While this was underway, Ivor returned to Quick Step to await JIS.
Our rigging method was similar to what we'd used before at Minocal's (Jan 15/05); we tied the monster-rope (100m long, 11+mm dense static) to a convenient, large tree and fed it into the hole. We used a rope-pad on the worst part, at the top, but otherwise the rope is so bombproof that it doesn't need to be babied. This was the main-line. Because we hoped to push the hole further than what the 100m rope would manage, we set aside a lighter 50m line to bring down the hole. In addition to these two ropes, a 60m 10mm line was arranged for use as a belay line, as it was out intention to get a videographer down, at least, to the first terrace of the pit. In theory, he would be on rappel, but he would be belayed on a separate line to prevent him from plummeting to his death if he lost his concentration. Lastly, a very long etrier was hooked into the main anchor that would be used for safety purposes at the top.
Not long after noon, JIS, and the others of our crew, joined us at the pit. Things were somewhat chaotic at first, but order was soon established. It should be noted that the JIS crew totalled five, we now had quite a few people on the scene, and we had fears of losing someone down the precarious perimeter of the hole. The first drop is about 55m.
On-camera interviews were done, decisions were made, and we then began the process of descending the pit. Two of the JIS team were interested in coming down, but it seemed best to limit it to one since it was their first experience with vertical gear. The chosen victim was Claude. Along with him, we intended to put Kimberly, Adam, Elizabeth, and Stefan into the depths. We'd done something similar at Volcano Hole, five people in a deep cave, with not everyone experienced, so we weren't concerned about the numbers. However, the JCO crew certainly knew at this point that we would not be out of the bush before dark.
First on rope was Adam. Unfortunately, a new descender he was using wouldn't accommodate the monster-rope. We tied another rope that we had to the main anchor, a 60m 11mm line. This just barely fit into his descender. He headed down, but after about 10m things were jamming up (determined later that the fit was so tight that it forced the sheath down the core of the rope until the diameter was too great to run through). We lowered in a 10mm line that he then changed over to and used to ascend back to the surface. It was decided that Ivor, using a figure-8 for rappel, would take his place on the descent team. Over the next half hour, we moved three JCO crew (Elizabeth, Ivor, and Stefan), Kimberly of TNC-J, and Claude of JIS, to the bottom of the first pitch. Claude was kept on a tensioned belay, but had no problems with his first rappel on a figure-8. Respect.
Another brief interview was done at the bottom (the camera had come down with Stefan, and Claude, the videographer, was already in the pit). Kimberly, last on descent, soon joined us at the bottom. Claude had decided that he would wait for us at the bottom of the first pitch, which was probably a wise decision on his part. The other four of us carried on down to the next terrace.
At the second step, it could be seen that water was pooled at the bottom of the third pitch, the current far point for this sinkhole. One of the team, Stefan, went down partway to have a look, and could see clear water pooled to a depth of 1-2 metres. This would put the surface of the water at about 82 metres below the entrance. It should be noted that it was the rainy season, and the shaft had been taking water on our way down, increasingly after the 65m point. The water input seemed to be at least somewhat underground, rather than all surface flow at the entrance. It is known that during the dry season the part of the shaft that was currently underwater extends lower, and is dry. Airflow has been noted below the second step. It is believed by the JCO that the sumped pool observed this day represented the top of a larger phreatic zone that varies in height seasonally.
The reasons for the above follow: The shafts found in the district are fault-based, and locations will be seen to describe lineaments. It would be expected that there is subsurface fracturing associated with the faulting that permits surface waters to drain from any associated shafts. Sesarma verleyi (crabs) are found in this sinkhole, with this species being troglobitic and incapable of surface dispersion. Most of the shafts in the Quick Step district are located in true cockpits, separate from other cockpits, on all sides, by saddles. Many of the cockpits that hold shafts and sinkholes in this fault-based system have been observed to flood into standing water for a long enough period to inhibit forest growth. This is a common occurrence in cockpits that have river caves entering and exiting (e.g. Rock Spring), but it is not common in the Cockpit Country in areas that have no surface flow.
We believe the significance of this is that the sinkholes of Quick Step comprise a connected hydrological system that may have been overlooked in the past. The water input is no doubt the abundant rainfall in this area, caught in cockpits that permit no surface flow. The limestone is poorly-bedded and has not allowed stream-passage development. All of the rains are caught, and the waters flow down into this zone of faulted development. In the case of Minocal's, it connects at a depth of at least 90 metres to other shafts. Cockpit bottoms that have lower elevations have the potential to flood from below, rather than the surface. We might have seen evidence of this at Sawmill Cave.
Once we were again assembled at the second step, having collecting what needed to be collected, and having done what could be done, we began our ascent. This would prove to be interesting.
The vertical from the second step to the bottom of the first pitch is not great, about 12m, but passes over a breakdown bridge en route that is overhanging and muddy. Nevertheless, the four of us, all experienced at muddy pitches, soon rejoined our JIS crew, Claude, at the bottom of the first pitch, 55 metres from the surface. Another quick interview had taken place as soon as the first of the JCO team reached Claude, and the video part of the session was now over. Now would come the part where we would send five people up 180 feet of rope, one of whom had never contemplated doing such a thing until today.
Storms had been brewing outside before any of us had even entered the hole. By the time we were in, it had started raining, and the booming of thunder had echoed down to us. By the time we began the ascent, the rain had become heavier and was beginning to become a real factor. The main problem was that our convenient anchor, up top, was above a funnelled dripline. This resulted in a little waterfall that came down upon those on-rope, especially those who came last when the storms and rains were very heavy. Along with this, we'd had problems with our walkie-talkies, and they were not useable. Because of the noise of the rain, and thunder, and the little waterfall, communications from top to bottom became impossible towards the end.
Ivor was first on ascent, to be at the top in order to assist the more inexperienced of our group, and then came Claude's turn. Considering that he had never used ascenders before (meaning that his very first ascent was 180 feet, freehanging in a rainy hole), he did splendidly. We must note that he doubted his abilities towards the end, but with a little encouragement managed to gather his strength and make it to the top. With our main concern now taken care of, it was only a matter of time. Elizabeth was next on rope, and she made good speed on her longest ascent to date. Next was Kimberly, who made the fastest time of the day, moving up quickly and steadily to arrive at the surface in less than 25 minutes. Last would come Stefan, hauling 40 pounds of video camera in a pack that hung from his harness. It was now necessary to pull muddy rope down through the ascender, every move, for the first 30 metres, because there was no way to supply downward tension for the last person and the muck on the rope caused the chest ascender to stick, rather than slide. This meant that there was only one hand available for the top Jumar when standing in the foot-loops. The extra 50m line that we had carried into the pit, in hopes of pushing things, had been tied to the end of the monster-rope so that all could be pulled out at once (Stefan not even able to contemplate carrying it up along with the camera) resulting in a lot of rope carefully laid in large coils at the bottom, with potential snags cleared as best possible. The rain was very heavy now, and the little waterfall was at its greatest. Much time had passed since the first of the cavers had headed up, and it was dark outside, in the bush above. The camera began its ascent from Minocal's Glory Hole, accompanied by the designated beast of burden. It was impossible to look up to gauge the distance remaining, because of the waters falling from above. The pack holding the massive video camera, that hung from the back of the harness, pendulumed with every move upwards, and every step was work. In short, the ascent was very difficult, it took about an hour, and it is hoped that this set of conditions will never be repeated.
The last of the team were out of the hole at about 8:30 PM, two hours after dark, and the collection of ropes and gear began. The rain was still beating down on us while we did this. Dr Lee, bless his heart, had stayed at the top of the hole the entire day, through the rain, until the last of our crew were out, and cannot be thanked enough. Ivor, of course, was still at the top, as was our local helper. The JIS people had already retreated to their SUV, parked at the start of the hike, but they had taken up some gear. Ivor, Stefan, Dr Lee, Elizabeth, and our assistant, hauled our many kilos of wet ropes, vertigear, and a massive video camera up to the cars, and after checking to see if we had everything, we journeyed back down the road to Joeanne and Hortense where food was waiting for us.
Biological observations at Minocal's follow: In the lower sections, below 60 metres, Sesarma verleyi are common, but few other inverts are found. Much of this part is very muddy. At the bottom of the first pitch, 55 metres down, there was quite the collection of terrestrial animals present during our visit. These included: a small snake, species undetermined at present but not a Yellow Boa; an unusual frog with distinctive colouration that was not a tree-frog; a large araneae (apx 7 cm across the legs), noted in other deep shafts (Anancy Hole, near Booth); and Buffo marinus (we remain somewhat mystified at how these large toads make it to the bottom of the shaft alive, having seen them in other pits as well).
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