Matienzo 2005

Cave exploration around Matienzo during 2005

Introduction to explorations up to the end of August
By the end of summer 2004, twelve months of exploration had produced over 10.2km of new cave passage, most of it in the newly discovered Sumidero de Cobadal. In contrast, by September 2005, twelve months of "exploration" had found only 2.7km. The reason for the dearth was a lack of permission from the authorities - in fact we were sent a document from the Consejería de Cultura, Turismo y Deportes, the permit-issuing body, stating we were temporarily refused permission to cave. After a supposed policy review, the Consejería de Cultura, Turismo y Deportes would not issue permits for caving in Cantabria without a Cantabrian cave rescue group in place, on the advice of the Servicio Protección Civil. The application for a Sports Council grant was withdrawn when it became clear that we could not be guaranteed a permit. Over the Easter period, many new cave entrances and digs were discovered as cavers turned walkers. At Whit, some superficial activities were carried out.

A rescue company was finally formed to the satisfaction of the authorities at the beginning of August, which is when the permit was finally issued. A number of visits to the offices in Santander from January onwards did not seem to have any effect on speeding up the process, although everyone appeared sympathetic. The result of all this was a lot of digging and adventurous walking during the first half of the year, resulting in 224 new sites of speleological interest, only some of which were explored in the summer.

Because of the uncertainty surrounding the permit the number of people who came to Matienzo were in the low teens compared with the hordes last year. Easter and summer were both dry and water levels in the summer were the lowest we'd seen for a long time.

One of the surprises during the summer was the extensions in the Cueva Risco System. The top entrance, Cueva Oñite (site 27), was visited with the intention of extending Mavrino Inlet. Just inside this on the eastern side a calcite-floored passage sets off. This went for about 100m with signs of previous entry to a low point which was dug out to a small chamber and a 5m free climb to a bedding plane, ending at the top of a meander passage.
On a second visit a climb above the meander passage entered a crawl with boulders that continued past holes in the floor and entered walking size passage with stal and passages in the roof. The passage rose to near the surface with tree roots: Gulag Gallery had almost come full circle back to the Oñite entrance with a length of 446m.
On a third trip, 184m of extensions on the opposite side of Mavrino Inlet provided the Sala Carballo Pitch Bypass. The total length of the Risco System is now 9676m.

On Enaso, a couple of hours were spent in the 31m of site 2153 where bear scratchings, crawling and tighter crawling, and fossilised breccia provided some interest. In Cueva Cofresnedo, some sediment samples were removed for possible future DNA testing. For the future, site 2324 is a pitch with a good stone rattle that requires a sandstone wedge removing.

In Llueva, site 1989, explored the previous year, was surveyed and photographed. The excavated entrance is on a ledge, 2m above a depression next to the road. A 12m pitch has a tight start then opens out into a large, well decorated chamber about 30m long, 20m wide and 6m high. The chamber is floored with large, dropped blocks with no obvious route through. Two flowstone inlets close down after a couple of body lengths.

The mountain of Muela provided a few holes with, as usual, a number still to descend. Site 2165 - a wide shaft discovered in the snow in February - was descended in the summer down 11m to a possible dig in a rift.
In site 2286, at the back of La Colina, a 12m roomy pitch dropped to a decorated rift and a low, 10m long passage under a wall - a fairly rare event on Muela. This choked at a calcited run-in that would be a straightforward dig.
Site 2338 dropped 12m to a choke.

To the south of Fuente las Varas, above Carcavueso, about a dozen shafts and digs require attention. These are all in a line cutting across the hillside and are associated with sandstone.

In site 2310, just inside the depression below Cruz Uzano, a tight entrance was excavated and a 6m pitch dropped to an impenetrable outlet.

Site 2139 was discovered in October 2004 as an entrance blocked with a couple of rocks behind which was a 3m crawl to the head of a 10m drop. This was investigated in December when one explorer descended a ladder to the floor and the other climbed over the drop and slithered down the rifts and boulders at the back. At the base, walking-sized, ascending passage headed northwest for a short distance to end at a tiny hole 5m up. In the other direction a 1 to 2m high chamber contained some nice formations and also some black pottery on the floor, probably Bronze Age.
With the idea of investigating the small hole at a later date, the 2 explorers left by the same routes. Half way up the ladder, a casual glance onto a ledge showed a human skull. This immediately brought the pair back together and a careful reconnaissance of the ledge and surroundings were made revealing more pottery.
With the arrival of the caving permit and an archaeological permit for Jesús Ruiz Cobo in the summer, the skull and all the pottery was removed from the ledge and floor, under the glare of 600W of video lights powered by a tiny portable generator.
Preliminary investigations have shown that another bone recovered from the floor is also human and that the pottery comes from at least 5 objects. The preliminary article, with diagrams of some of the pottery, can be seen as a pdf file.

Cobadal and possible links with Matienzo or Fuente Aguanaz
The main aim for the year was to investigate any feeders to, or outputs from the Sumidero de Cobadal.
The water at the end of Cobadal cave sinks in the floor at the base of an 11m pitch, a kilometre to the south east of the entrance and some 75m deeper. There are two apparent resurgences, Los Boyones - 6.3km to the northeast - and Fuente Aguanaz - some 4.3km to the northwest of the disappearing water. The passages in Cobadal have been progressing nicely towards the Matienzo depression before the water sinks. If the water resurges to the northeast, it must feed the 43km Four Valleys System, the nearest passages of which are about 2.5km away. If Cobadal feeds Fuente Aquanaz the water in the Cobadal passages will need to reverse direction. The water in the cave system sinks at 125m altitude; both resurgences sit at 50m altitude.

The intentions for Cobadal during 2005 were to
1 attempt a dig in downstream Cobadal
2 attempt further digging in the boulder choke high above the downstream outlet in Cobadal
3 push any other leads in Cobadal
4 push upstream in the Wessex Inlet towards Torca de Regaton
5 explore passages in Torca de Regaton which may feed into Cobadal
6 investigate the La Gatuna area which may well feed into an easterly flowing Cobadal system
7 further investigate the Cobadal area, both on the surface and underground
8 further investigate ground to the east of Cobadal where Regaton, Cobadal and the 4 Valleys System appear to come close together
9 investigate the possibility of water tracing in Cobadal.

A dig at the bottom of Cobadal was not attempted but the boulder choke above was revisited and further upwards progress was made, following the draught.
In the higher, southern Cobadal passages, the small Evidence Oxbow Series Extensions produced over 200m, leaving the Sumidero de Cobadal with a 6267m length.
In the low, wet and draughting bedding called the Wessex Inlet, protracted hammer and chisel work has gained a few metres of 0.5m high passage to where the cold explorer is surrounded by water on a small calcite boss. The draught is coming through small gaps and further work now requires wet suits.
It is thought that the 17km North Vega System (which includes Torca de Regaton) may feed into Cobadal and a number of trips pushed a number of passages in the northwest section of the North Vega System. A resurvey also cleared up the mess surrounding 50m Error Passage. In all, 647m of new passage were surveyed: one passage paralleled the 50m Error Passage and one headed east under Cueva Morenuca. About 70m were grade 1-surveyed through a tight squeeze into bigger passages and chambers vaguely heading towards Cobadal.
The La Gatuna area is an enclosed depression 1.3km north to south, about 0.5km wide at the widest point and containing many other smaller depressions. The speleological interest lies in the number of draughting holes at low level and the fact that water from the depression may well drain south to enter supposed easterly passages in Cobadal. What makes La Gatuna something of a challenge is the thick, brambly vegetation and the thick beds of sandstone.
The area was first investigated in 1979 when Cubio de la Gatuna (site 127) was explored and surveyed. In the spirit of re-exploring and pushing known sites, this cave was pushed into Ann Summers - a well decorated section, and extended by 120m to a length of 285m. A nearby draughting hole (site 2223), discovered at Easter, was opened up to provide a 3m climb into a 130m long cave with some walking sections.
Of the 76 documented sites in La Gatuna, 34 are digs: many are draughting and some were dug. Among the more intriguing is site 2222, where a draughting crawl was dug and then abandoned only to discover another draughting hole just inside the entrance.
The Fridge Dig (site 2227) is a brick and stone construction with a wooden and shelves inside sitting over a small hole up through which blows a cold draught. Negotiations with the owners have yet to occur, but a small video camera lowered down below the grilles shows at least one tiny, draughting hole.
There are 15 unexplored sites - both shafts and caves and a number of other holes which merit further investigation, the main one being Cueva de Collada. This cave was first entered in 1982 and explored over 3 days. The stooping-sized entrance takes a tiny stream at the southern end of the La Gatuna basin - the point in the depression closest to Cobadal. After about 50m, flat out crawling through a tight section reaches the head of an 8m pitch with tight passage beyond that ends at a 5m drop. The water then drains down a sinuous rift that hasn't been pushed to a conclusion. However, the main interest lies in a 7m high passage that heads south east. This enters smaller passage and draughting breakdown.
An attempt was made to drop the first pitch and a new bolt was put in this side of the squeeze - but the head of the pitch needs opening up. With its draught, water and good development, Cueva de Collada has to be the prime site for pushing with modern digging techniques.
At a higher level, on the western side of the depression, a number of holes have been documented that need entering or digging out. Most of these lie under sandstone beds - the sandstone forming the roof of a dissolved joint or bedding in the limestone below. One wide shaft (site 2189) at the base of a shakehole was descended 7m onto sandstone blocks and a choked floor with gaps between.

As part of the wider look at the Cobadal depressions, more walking and underground exploration took place at the periphery. Of the 77 sites around Cobadal, 21 are documented as digs and 17 as unexplored. One explored in the summer was Woodcutter's Cave (site 2183). This is a resurgence near to Snottite Cave, where the water sinks almost immediately at a major dig. Inside the 4m high resurgence entrance, the passage straight ahead is a fine phreatic tube with trench which immediately swings to the right behind 2 dams to the water source - a tiny passage with strange acoustics. To the left, just inside the entrance, a stooping passage decreases in size at a black mud inlet corner and then become crawling between mud walls which collapse into the streamway trickle. This makes for a fairly clean inward journey but a very muddy exit. About 100m from the entrance, an excavated section enters a relatively impressive pair of 12m high, drippy avens. The streamway continues small beyond and requires some easy excavation in similar passage at "station 0".

With the notion that Cobadal water may come east, picking up water from the North Vega System on its way to the Four Valleys System, the draughting caves and digs off the first bend near site 415 have even more significance. The Pants Dig (site 1655) was attacked with some enthusiasm throughout the year and Boil in the Bag (site 868) was similarly enlarged where the whole draughting hole may be sitting on a boulder choke into the back end of Cueva Bollón.

When the water in the Sumidero disappeared into gravel 4 and 6km from possible resurgences, it was obvious that a water trace needed to be carried out. Unfortunately, both possible springs are public water supplies. This year we made contact with the Dirección General de Obras Hidráulicas y Ciclo Integral del Agua in Santander where a very useful exchange of information took place along with discussions as to the best way to determine the Cobadal water resurgence. A written general proposal has been made and a more detailed proposal will follow, possibly utilising the Water Board's resources.
(One interesting set of data showed average water flows at the surface only. For example, Carcavueso is shown with 295 l/s sinking in the Matienzo depression and 650 l/s resurging at Los Boyones. Most of the "missing" water must come from Cuevas Riaño and Hoyuca. Fuente Aguanaz is shown to have 951 l/s average flow and here there is only a single 1.7km passage known, with no known surface inputs).

Alisas, South Vega and Cueva Vallina
The "new area" from last year, to the north of Alisas, could also drain to Fuente Aguanaz and a number of shafts were looked at this year. Twenty five were documented at Easter and a number of these descended in the summer. Cueva Amarillo (site 2270) with a length of 28m was one such hole but more interesting was 2264. This had clearly been descended by another group down 18m and 14m pitches to the head of another bolted pitch. In the opposite direction along the rift was an undescended blackness with a draught.
A number of these sites around Alisas have been descended by another group and some have been marked with "CA" and a number with a red square either empty, with one line or a cross presumably to show the state of exploration. All are being descended because, for example, site 2264 mentioned above (CA4 with red square and cross) appears to be undescended in parts.

In more familiar territory, above the South Vega System, a Sunday morning visit was made to site 1219 where Tiano, who farms the area, pointed out a covered shaft on the side which seemed to be 40 or 50m deep. This roomy shaft (site 2287) was uncovered and descended in the summer when it was found to choke. A double-barrelled shotgun without the woodwork was recovered.
Near to Sima Reguilon (site 46), site 2311 was uncovered and promised much at the bottom of a 13m entrance pitch. A chamber with a wide passage and calcite slope had a dry streamway which was followed to a bowl-shaped chamber where "Sick Joke Pot" finished as the water sinks away. Upstream the passage quickly divided into a series of inlets.

Other sites investigated included 2127, a 50m choked shaft left over from last year; 2097, a roomy shaft that descended 16m to narrow, choked rifts; site 2094, a 29m deep choked shaft; the wide but shallow shaft at site 2352; and another "sick joke" at site 2342 where a 15m drippy pitch dropped down a fine echoing shaft over an 8m high calcite wall to a tiny outlet. Site 782 was finally hammered open (15 years after the initial discovery) to a tight squeeze that entered a 10m pitch to a slope and 5m of passage to an aven - another sick joke!

One of the sites still to be investigated lies in the middle of a pathway in a well trodden area over Cueva Vallina; site 2306 is a boulder-capped shaft of about 12m depth. This find shows that every square metre in our 156,000,000 m² area needs to be investigated and no stone left unturned!

In Cubio de la Reñada, a trip to the aqueous Squirrel's Passage and Moat of Doom area revealed deep blue pools that require diving. The whole area needs people in neoprene.
The old Bolton Speleo Club dig, Cueva de los Tablons (site 242) first found in 1978, was opened up again and much progress was made down and into the hill along a hading bedding or joint. A strong, cold draught blows out between blocks and mud at about 6m depth. This is in a prime spot to "go anywhere" to the east of the South Vega System.

In Cueva Vallina, the major route discovered last year through the Barney Rubble crawl was finished off when most leads were pushed to a conclusion. Over 200m were added to the length of Galería de Germán. Passages off Swirl Chamber were also surveyed to a length of 172m. Cueva Vallina now has a length of 32954m and is the 11th longest in Spain.

Conclusion to the main expedition periods
A difficult but quite satisfying 8 months to the end of August. The lack of permit obviously dampened down the exploration fever from the previous year but a lot of work was put in finding new sites and digs for future exploration. Unfortunately, at the moment, there is no guarantee that the current cave rescue company will land the contract for next year, so there is likely to be another period of uncertainty before a permit is issued.

The list below shows links to those 274 sites which were extended or newly discovered over the first 8 months of 2005, or which have had surveys updated, entrance photos or movie clips added, or entrances repositioned with a GPS.
25 Risco, Sima-Cueva del; 27 Oñite, Cueva; 48 Reñada, Cueva-Cubío de la; 65 Cofresnedo, Cueva de; 77 Rascavieja, Cueva de;
Carcavuezo, Cueva de; 127 Gatuna, Cubío de la; 129 Muela, Torca de la; 155 Lara-Lennon, Cueva de; 169 cave; 242 Tablons, Cueva de los;
Beauties, Cave of the; 394 Collada, Cueva de; 402 shaft; 465 shaft; 484 Zorro, Torca del; 490 shaft; 545 shaft; 559 shaft; 602 shaft;
cave; 607 shafts - 4; 635 shaft; 679 shaft; 733 Vallina, Cueva; 782 shaft; 806 cave & 2 shafts; 868 dig; 892 Regaton, Torca del;
cave & shafts; 1062 cave; 1072 Famous Five Cave; 1128 Vacunación, Torca de la; 1129 cave; 1142 -; 1154 cave; 1191 shaft; 1192 shaft;
1213 Tib Pot; 1216 shaft; 1217 shaft; 1219 shaft; 1235 Roja, Cueva; 1272 shaft; 1278 shaft; 1333 Tortilla, Torca; 1386 dig; 1523 cave;
cave; 1550 shaft; 1584 shaft; 1585 shaft; 1601 depression; 1609 shaft; 1629 shaft; 1631 dig; 1632 cave; 1636 shaft; 1638 shaft;
shaft; 1646 shaft; 1647 dig; 1648 shaft; 1649 shaft; 1655 dig; 1830 cave; 1875 shaft; 1930 Cobadal, Sumidero de; 1949 cave; 1979 shaft;
cave; 2015 shaft; 2016 cave; 2046 shaft; 2094 shaft; 2097 shaft; 2139 cave; 2158 shaft; 2159 shaft; 2161 shaft; 2165 shaft; 2166 shaft;
dig; 2168 dig; 2169 dig; 2170 shaft; 2171 shaft; 2172 dig; 2173 collapse; 2174 shaft; 2175 shaft; 2176 shaft; 2177 depression;
Slow-worm Hole; 2179 Badger Hole; 2180 Well Dressing Hole; 2181 collapse; 2182 depression; 2183 Woodcutter's Cave; 2184 sink;
Double Horse Trough Rising; 2186 cave; 2187 dig; 2188 dig; 2189 shaft; 2190 shafts; 2191 dig; 2192 dig; 2193 shaft; 2194 shaft;
shaft; 2196 shaft; 2197 shaft; 2198 shaft; 2199 shaft; 2200 shaft; 2201 shaft; 2202 shaft; 2203 holes; 2204 shaft; 2205 shaft; 2206 shaft;
dig; 2208 shaft; 2209 shafts; 2210 shaft; 2211 hole; 2212 dig; 2213 dig; 2214 dig; 2215 dig; 2216 holes; 2217 cave; 2218 cave; 2219 dig; 2
cave; 2221 shaft; 2222 cave; 2223 cave; 2224 dig; 2225 dig; 2226 Lunchtime Hole; 2227 Fridge Hole; 2228 dig; 2229 dig; 2230 dig; 2
dig; 2232 shaft; 2233 shaft; 2234 cave; 2235 dig; 2236 shaft; 2237 shaft; 2238 cave; 2239 cave; 2240 shaft; 2241 cave; 2242 dig; 2243 dig;
dig; 2245 cave; 2246 dig; 2247 dig; 2248 dig; 2249 dig; 2250 dig; 2251 dig; 2252 collapse; 2253 shaft; 2254 dig; 2255 dig; 2256 shaft;
cave; 2258 shaft; 2259 cave; 2260 shaft; 2261 dig; 2262 dig; 2263 shaft; 2264 shaft; 2265 dig; 2266 shaft; 2267 shaft; 2268 shaft;
shaft; 2270 Amarillo, Cueva; 2271 shafts; 2272 shaft; 2273 dig; 2274 shaft; 2275 shaft; 2276 shaft; 2277 shaft; 2278 shaft; 2279 shaft;
shaft; 2281 holes; 2282 shaft; 2283 shaft; 2284 dig; 2285 shaft; 2286 shaft; 2287 shaft; 2288 cave; 2289 shaft; 2290 resurgence; 2
shaft; 2292 dig; 2293 dig; 2294 dig; 2295 shaft; 2296 shaft; 2297 cave; 2298 cave; 2299 shaft; 2300 shaft; 2301 cave; 2302 cave;
depression; 2304 shaft; 2305 shaft; 2306 shaft; 2307 cave; 2308 shaft; 2309 shaft; 2310 shaft; 2311 cave; 2312 caves; 2313 cave;
dig; 2315 cave; 2316 cave; 2317 cave; 2318 shaft; 2319 shaft; 2320 Catskull Cave; 2321 holes; 2322 dig; 2323 cave; 2324 shaft;
cave; 2326 shaft; 2327 cave; 2328 shaft; 2329 shaft; 2330 shaft; 2331 shafts; 2332 shaft; 2333 cave; 2334 cave; 2335 shaft; 2336 dig;
shaft; 2338 shaft; 2339 cave; 2340 cave; 2341 cave; 2342 shaft; 2343 cave; 2344 cave; 2345 cave; 2346 cave; 2347 cave; 2348 cave;
cave; 2350 dig; 2351 dig; 2352 shaft; 2353 cave; 2354 shaft; 2355 shaft; 2356 dig; 2357 dig; 2358 dig;

Autumn activities
A couple of trips into Cueva Collada in October saw the first pitch tackled up and a new bolt put into the head of the second pitch. A thin coal seam was also recognised in the entrance crawl and probably modern pottery found above the first pitch head.
Of three new sites found, number 2360 appears the most promising - a 10 to 12m pitch with a good echo.

The list below shows links to those 10 sites which were extended or newly discovered over the autumn of 2005, or which have had surveys updated, entrance photos or movie clips added, or entrances repositioned with a GPS.
109 Cellaron, Torca de; 394 Collada, Cueva de; 487 Statua, Cueva; 489 cave; 713 Aguanaz, Fuente; 1069 shafts;
cave; 2359 shaft; 2360 shaft; 2361 cave;

A small team visited the area over the San Martin fiesta weekend in November. Cueva Collada was extended down the meander at the base of the second pitch to the head of 12m undescended drop. Upstream was surveyed for about 100m in passage 1m wide by 12m high until a boulder choke was met.
More digging took place in Cueva de los Tablones and site 602 was finally uncovered and descended down a 15m free hang, 19 years after its discovery. Cueva Candanosa was pushed along the crawl to a conclusion and Torca Candanosa was descended to a passage which choked. The Volcano dig was excavated and a 16 hour trip in Papá Noel to the Hall of Tubes area found no new passage, although some surveying was carried out. Frank's Cave was also further excavated.
Over Christmas, Cueva de los Tablones was dug.

The list below shows links to those 9 sites which were extended or newly discovered during November and December 2005, or which have had surveys updated, entrance photos or movie clips added, or entrances repositioned with a GPS.
242 Tablons, Cueva de los; 394 Collada, Cueva de; 602 shaft; 681 Candenosa, Cueva; 682 Candenosa, Torca; 1391 Volcano Cave;
cave; 1471 Papá Noel, Torca de; 2167 Frank's Cave;

Juan Corrin, September, November, December 2005

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