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The visit last weekend to Rock Spring by Dr. I.C. Conolley, Prof. S. Kouwenberg, J. Pauel, and R.S. Stewart was very productive. We descended what we've been calling Big Hole, which was about 80m deep in two stages, and reached the start of the Grand Gallery. It needs a bit of checking, but it seems Big Hole may be Hole 2 on the Leeds map, and Scary Hole is Hole 5. If we're right on this, it means the bottom of the first stage, about 50m vertical, will give access to the upper parallel passage that leads to a scramble down near Hole 5 making it the fastest way in/out of the upstream part of the system. Indeed, we did see a passage on the west side of the first stage that we suspect is it, although time constraints prevented exploration.
The plan for the next visit is to again descend the first pitch of Big Hole and see if our assumptions are correct.
Our last outing, at Rock Spring over Christmas, was stymied by a flooded entrance, but we'll be back there this weekend to check one or two of the new holes we've found that might lead down into the main system. More to follow early next week.
We've produced a sketch map of Rock Spring North, first explored on November 28, based on compass bearings and distance/slope estimates recorded by Stewart, which can be see below. The entrance pitch slopes somewhat to the SW in the lower half. The small alcove at the NE end was choked with blocks that had fallen from a shaft above of undetermined height, and might have had a slight airflow. A video of the outing can be found at Rock Spring North and Tiny Hole on YouTube.
Kouwenberg, Pauel and Stewart were back at Rock Spring on November 28, this time investigating one of the new holes we've found, Twin, so named because of two openings at the top created by a large chockstone sitting over a shaft (area map here). After descending and exploring it, we now know that it's an entirely separate, unlisted cave, and so are giving it the name Rock Spring North.
Rock Spring North is a shaft to a cave, with the shaft about 80m deep, and the cave at the bottom extending in two directions - about 30m to the NW, and 20m to the NE - with a height ranging from 2m to about 12m. Development as with Rock Spring Caverns is in joints with no obvious bedding planes. An absence of wall-scalloping indicates it was never an active stream passage. The elevation of the top of the shaft is high compared to the downstream shafts into the Caverns, so even with its great depth, it is likely still on a higher level. We'll do some GIS work this week to sort things out. Thanks to the many GPS tracks we've recorded while searching the surface, we can create a fairly decent digital elevation model for the area.
A moderate bat-roost (about 500-1000 individuals) is present that seemed to consist entirely of Artibeus jamaicensis. Cave crickets (Uvaroviella cavicola) were noted, as well as several roaches that may not have been the invasive P. americana (we're checking into it).
A sketch map will be posted soon based on approximate vectors recorded during the visit.
A second of the new holes, Tiny, was also investigated, but unfortunately it constricts into a tight slot, about 2.5m long and 20cm wide, 3m down. It was a little wider at one end, so passing it may be possible on descent, but ascent will be difficult. We'll keep it in mind, but for now it's on the backburner.
We'd like to wish everyone a good Heroes' Day, despite the 3:00 PM curfew in effect today. In fact, this time, 2020, the year of the pandemic, we're all being heroes by being sensible and staying in our yards. This thing can, and will, be beaten.
A short video has been put on our YouTube channel of wall scalloping at Rock Spring Caverns. Scallops are very cool; they form from turbulence on the walls of flooded, phreatic, passages, and indicate flow direction and velocity. In old, dry passages, where flow has moved lower or stopped, they show what happened in the past.
We've started work on the Cockpit Country cave report for JNHT and UNESCO. To give an an idea of how many sites are involved, have a look at a QGIS map export above. There's whole heaps.
We neglected to mention the first paper that was published on the fieldwork at Home Away and Schwallenburg caves. The Smithsonian had an article on it, and the paper is here.
The JNHT contacted us last week with regard to caves in the Cockpit Country Protected Area (CCPA), which is being added to the UNESCO World Heritage List. Our task is to clip the sites out of the master database, consult our records, and then put the information into an appropriate form. As there are over 100 caves and sinkholes in the area this will take some time, but we hope to have it ready next week. A public version will be posted soon after.
The JCO has just been mentioned in an article in EOS that discusses a recent paper in Quaternary International that resulted from fieldwork we carried out in 2012.
In other news, we hope to get back to Rock Spring soon, but the Covid-19 curfew here in Jamaica is still making timing difficult. In the meantime, we'll post a short video on the YouTube channel in the next day or so on wall scalloping at the cave.
Kouwenberg, Pauel, and Stewart were back at Rock Spring last Saturday and finally established the route from the dam entrance to the much more extensive upstream part of the system. It turns out that we were very close last visit, July 25, but neglected to explore a connecting passage. Not surprising, since it's in the appropriately named "Labyrinth". We've left it well-flagged, so next time shouldn't be a problem.
How we did it was to enter upstream through "Bamboo Hole", and then descend about 60m through two stages to reach the river. From there, we headed downstream and refound the constricted opening that leads up into a very large batroost that had been the limit of our previous downstream exploration (excluding the July 25 dam visit - video on YouTube). Carrying on, within 10 minutes we came across one of our flags from July 25, and knew we'd nailed it.
Time was tight because of the ongoing curfew, so we were unable to sort out all the passages and junctions in the Labyrinth, but instead went directly to the dam entrance. Here, the water was about 5cm higher than last time, but there was still enough airspace to get out without diving through a sump.
After exiting the dam, we hiked directly toward Bamboo Hole to retrieve the rope, up a very steep hill, and amazingly found yet another deep hole on the way that must lead down into the cave. This makes 14 now, although only 7 were shown on the original survey. We've completed full descents of 3 of them, but plan to knock them all off as time permits. We have to wonder if some may lead into unexplored territory.
Noel Levy, of the Jackson Bay Hunting and Fishing Club, joined Jan Pauel and Silvia Kouwenberg, of the Jamaican Caves Organisation, at Jackson's Bay, Portland Ridge, Clarendon, yesterday to offer some advice on how we may find the Taylor's Hut caves.
Noel knows the area very well, including old, vague, seldom-used tracks. We're very grateful for his help, and will resume our search as soon as we finish up Rock Spring.
We've posted "Jamaican Caves Organisation Occasional Publication 1 [Public Edition], ISSN 0799-6275", a comprehensive summary of exploration and research at the caves of Jackson's Bay and west Portland Bight, Clarendon.
In the public version, here, The Caves of Portland Ridge, Jamaica - PDF, we are reserving coordinates in aid of site protection. Interested parties may contact the Jamaican Caves Organisation at firstname.lastname@example.org for further information.
Today marks 18 years since the website went online. The site admin, Stewart, had no idea what he was doing at first, which explains the bizarre navigation, but now, with about 500 pages on the server, it's difficult to improve things without disappearing from certain search engine queries. It is what it is. So, we'd like you to think of the website being somewhat like a complex cave - wander around, try to keep track of the route, and see what you stumble across.
Speaking of complex caves, we've put a video of our latest outing at Rock Spring on YouTube. Jan has had a version ready to go for weeks, but YouTube is making it difficult (impossible, so far) for him to upload it. It's demanding he enter a code that is supposed to be sent as a text message, that it never sends. We haven't given up battling the idiots (Google, the monopolistic monster trying to control the part of the internet Zuckerberg doesn't own), but for the time-being, Stewart, who first put the channel online, has created a shorter, lower-resolution version using Shotcut, and sent it up.
We hope to have the Portland Ridge report online soon (cover photo to the right). Just needs some final tweaking.
Our visit to Rock Spring last Saturday was cancelled due to rain from Laura (passing tropical storm), and a resumption of an early curfew in St Catherine and St Andrew that runs through Sept 2, and possibly longer if the Covid-19 surge continues.
We've updated the Jamaica Cave Register page, and added several maps to put the positions into context, one of which, geology, can be seen below. Click on the image for a high resolution version.
Note that in the register coordinates are given only in JAD69 and JAD2001, not lat/long. This is intentional to make it a little harder for people to find them. One can't simply enter them into a GPSr - they have to be converted first. It's our assumption that genuine researchers will be more capable of doing this than casual tourists.
The plan is to return to Rock Spring Caverns this weekend to continue probing the mysteries of the somewhat baffling system. Amongst other things, we hope to finally traverse the connection between the upstream and downstream parts already visited.
Unfortunately, we (Kouwenberg, Pauel, and Stewart) had no luck finding the Taylor's Hut caves at Portland Ridge last weekend. Our hoped for location, derived from the georeferencing of an area map sketched by James Lee decades ago, yielded nothing but macca, and jagged, highly-eroded rock (think of a widespread, limestone crumpet with razor-sharp upper edges). Three of the four surrounding quadrants were covered out to about sixty metres before we gave up due to south coast, August sun beating down on us.
However, it wasn't a total loss, as we did spend a very pleasant night on the beach afterwards.
Hunting season starts next weekend, so there'll be no more visits to the ridge until it's over in a couple of months. During the interim, we'll be back at Rock Spring.
We'll be back in the field this weekend, this time at Portland Ridge, south coast, in an attempt to find the Taylor's Hut sites. If we're successful, it will finish the baseline data for the upcoming paper. There are two sources of positional data that give us hope: an area map from Lee's investigations that we've georeferenced, and a likely looking location on Google Earth. As usual on the ridge, it will require a systematic search that will include much bush-whacking through much macca. So it go. Wa' fi do. If things go well, we'll have positive results to post next week.
There's no fieldwork this weekend, but we plan to return to Portland Ridge the following week to hunt down the Taylor's Hut caves, which will complete the last of the important sites on the ridge before we share the forthcoming paper.
We'd like to wish everyone a good Emanicipendence, and also big up our bredren and sistren island-wide for dealing with the pandemic so well, so far. But let's not let our guard down. It's not over 'til it's over.
We had an interesting day at Rock Spring Caverns, St Mary, yesterday. After many visits, for the first time, we entered the system via the dam entrance rather than one of the many deep, upstream shafts that also give access.
The delay was due to concern about flooding that would make it impossible to exit the same way if heavy rain fell while underground. We're now more aware of the possibility, having seen it from the inside, and realize it's not a problem. The adjustable weir that controlled the water level is siezed because of rust and inattention at a low position, and presently the entrance will only become a "duck" (having to pass through it entirely underwater) during tropical storms.
As can always be expected with the cave, it was confusing. We had hopes of connecting with our furthest downstream point, reached by way of the shafts, but this was not to be. The issue, again, was development on several levels. Our best guess at continuation was a higher level link at Confusion Chamber that required some sort of direct aid to ascend. The only rope we'd brought, a 25m 9mm static line, was left as a guide at the entrance in case of flooding, and none of us chose to attempt the scramble on bat guano covered slabs and flow-stone lest a slip cause serious injury.
At the end of all of this, we'll post a paper that goes into great detail on the system, but for now we'd like to give a basic description.
The cave has formed in an outcrop of strongly-jointed white limestone (karstic) that sits on impervious yellow limestone. Development seems to have first taken place at the higher levels, possibly entirely hypogenic, then migrated lower and became vadose, followed by collapse holes at the top of the joints. There are layers of cemented gravels, including metamorphic stone, that are in place on the walls in higher parts of passages and eroded along distinct lower lines that show long-term flow levels, which reflect the effects of one or more interglacials and associated climate change. But, as the cave has now bottomed out at the yellow limestone basement, in the future it may be limited to horizontal development (later generations of the JCO will follow up on this in a few thousand years).
Science aside, two young, strong, brave local boys decided to join us for the exploration - Roshane and Raheem. They were both champions, curious, and we have their contact info. We hope to have them with us again at Rock Spring.
Heavy rain prevented fieldwork at Rock Spring last Saturday (river cave - flood risk), but we'll make another attempt this weekend. For now, we'd like to share an illustration of the source of our confusion exploring the system.
The image below (click on it for higher resolution) has on the left the positions of all the holes we've found, and on the right the holes shown on the Leeds map from 1963, with orientation and scale matched. As can be seen, little of it makes sense. Are we finding holes that lead into a different cave in the north (our three full descents have been in the south), or is the Leeds survey misleading? The only way we'll know is by descending everything found so far, and as the three we've gone down were all over 60m to the bottom, we have a lot of rope work ahead of us.
We've been comparing the positions of the new holes found at Rock Spring, St Mary, last weekend to the 1963 Leeds University map, and it's clear that although the map is helpful in route-finding underground, when projected to the surface, it's inaccurate. Seven holes are shown on the map, we have now found 13, and none of those make sense when attempting to georeference the cave map using our GPS positions. In fact, we can't establish a definite match between any holes shown on the map and any of our 13.
Because we like a challenge, and exploring new pits, we'll be back there this weekend.
Our apologies for the lack of updates to the News. The JCO has been busy, but the site administrator, Stewart, has been lax in his duties. This changes now.
Kouwenberg, Pauel, and Stewart were back at Rock Spring again last weekend, this time for more recon of the many holes that enter the system. We have now found 13, although only 7 were listed, and are pretty sure there are two more shown on the Jamaica Underground map that we've yet to find. It's bizarre - we wander around in the bush in the general area above the cave, and stumble across hole after hole. Five this time.
So far, we've made complete descents of three of them, and partial descents of several others. Exploration of the cave itself has been to the terminal upstream sump, and most of the way to the downstream dam entrance.
A return in the next week or two is planned.
Also, we've just about finished a comprehensive paper on the caves of Portland Ridge, Clarendon, that will be shared with various parties. It includes exact positions for most of the sites, so we probably won't post it online, as is, to avoid inviting inappropriate visitation to very important caves, but rather a version with positions stripped out.
More to follow.