Jamaican Caving Notes
Aug 20, 2003
DEESIDE ROARING RIVER CAVE
Position: WGS84 - 18 23' 19.0" N, 77 44' 50.7" W
Field notes: R. S. STEWART
Cavers: R. S. Stewart, M. Taylor, R. Sterling
After we'd found and entered Valley Pit, we drove back down to Deeside from Chatworth to have a look at Deeside Cave. We hadn't been into it since June 13, 2002, and I was very interested in seeing what was happening in the river pit.
There were four of us in all, Ivor Conolley, Martel Taylor, a friend of Ivor's, Rona, who was lending a hand, and myself. Because of the off-chance of someone removing the rope at the first drop when we were further into the cave, Ivor decided to stay at the top of the pitch. Rona, Martel and I rapped down.
To give a quick review of the physical nature of this cave, I'll describe the main route in: The cave entrance is located on a hillside near a resurgence that is at a sharp turn in the road, not far from Deeside, on the way to Springvale. An entrance chamber of about 6 metres diameter gives way to a west-trending passage of about 2.5 m that soon ends in a squeeze through a stal barrier. After this squeeze, a short distance along a rifted passage brings one to the top of a vertical of about 10 metres. This is where Ivor remained. At the bottom of this vertical, a large passage ends in a crawl through stals to the south. This crawl brings one to a T-junction, the eastern branch ending in choked chamber, the western branch taking one up a talus slope that leads to the Canyon. At the western end of the Canyon, a finely decorated chamber conceals a squeeze, through stals, that leads to the River Pit. I'd been fortunate in having the sound of flowing water to allow me to find this squeeze on my first visit to the cave, otherwise I might not have found it despite the map in JU. On my previous visit to the cave, Jun 2002, the water was sumped up so high in the pit that there was no noise being produced by water, and once again this time, there was no sound to be heard from the Canyon end of the squeeze. It actually took me a few minutes to relocate it even though I'd been through it twice before.
The rap down the pitch had gone fine and we slowly worked our way towards the river pit until the three of us were gathered on the ledge high above the waters of the pit. This time, there was the sound of just minor trickling in the depths below. The water level was well above the levels of Feb 23, 2002, and some metres below what we had observed on Jun 13, 2002. To summarize: In Feb, 2002, the water levels were low so the river was only partially filling the initial part of the passage that takes the downstream waters of the underground river that passes through the pit, thusly creating a terrific roar of water in the depths below, and clouds of mist drifting upwards, as the river dropped over rapids to the downstream sump. In Jun 2002, the water levels were so high in the river chamber that there was absolute silence, except for an occasional drip, the passages below being totally drowned in the depths. This visit, Aug, 2003, the downstream passage was almost, but not entirely, submerged.
An interesting byproduct of this change in water levels is that there seems to be an associated variability of the breeze felt at the first stal barrier encountered after the entrance. The temperature of the cave varies accordingly. In Jun 2002, the temperature was markedly higher than either of the other two visits. Simple exterior heating of the overlying rock should have resulted in warm temperatures in Aug, but although it wasn't as cool as Feb, it was much cooler than Jun 2002, a time of high rainfall and little sun. In effect, the temperature of the cave seems to be inversely related to the level of the water in the River Pit. The notes by Atkinson from 1967, (the month isn't given in JU), indicate low water levels in the pit and a strong airflow outward from the stal barrier. They also describe a downstream sump in the River Pit during their visit but it is not stated whether the passage to the resurgence would have admitted air. The passage that continues west, from the ledge above the pit, and eventually chokes close to the surface, is above the level of the entrance. This implies convective airflow originating via the resurgence and River Pit when water levels are low enough. An attempt at determining if this effect is real, and if it can be quantified, should be made in the future.
We returned to the bottom of the pitch, and first Martel, then Rona, jumared up. I stayed at the bottom until last to advise Rona on her ascent; this was her first time using vertigear and Ivor had belayed her with a second rope for both the descent and the ascent. She managed quite well, with my coaching her from the bottom, and then Ivor from the top.
We hauled ropes and exited the cave.
N.B. to self: Discuss with SK a specific project monitoring changes in numbers of indicator species as related to phreatic/airflow/temperature dynamic.
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