The 1981 Expedition

A summary of the cave explorations which occurred in Matienzo during 1981

amended from an original article by Juan Corrin in Caves & Caving 14

The exploration of a new system accounted for over half of the 5.3 km of passage surveyed. Sixty new holes were investigated.

   At the end of 1980, Cueva Llueva (site 114) and Cueva Uzueka (site 107) were 170m apart. A smoke test was carried out early this summer (using 2 large flares) in the boulder choke at the end of Uzueka. At the same time a team of tour (John Palmer, Phil Papard, John Thorp and Fred Winstanley) were beyond the upstream sump in Llueva . . . "John and Fred made a thorough search of the large chamber and a small calcited passage was looked at, but soon choked. They then sat around waiting for 6.15 and the smoke. Phil was amazed to find that the diving line he had put through the boulder choke last year for route finding had been torn to pieces. Lugger in the mean time had started to climb upwards and had found a walking size passage. He returned for the others and again a diving line was laid to help route finding on the return. Walking passage lead off to a climb between a couple of boulders into a huge passage with a few holes in the floor. At this point John said that he could smell cordite. Boulders were dropped through various holes and then a climb down was found into a rift. This was explored in gathering gloom as the air became thick with smoke. The rift petered out and a blundering return was made, difficulty being encountered in visibility that was down to Sm or less. Once back in the chamber, the air was almost clear and an uneventful return to the sherpas was made..."

   On a later visit the first part of the extension was surveyed and then pushing on revealed a second major boulder choke that has still to be passed. Llueva and Uzueka are now about 70m apart. The draught from Uzueka appears to enter Llueva and then rush off through unpushed holes toward the Matienzo river sink cave about 600m away.

   A number of shafts in the Fuente las Varas area were descended but as usual these choked, as did 3 draughting caves above the resurgence at Secadura.

   The western arm of the depression (La Vega) received a great deal of attention this year. Work started with the surveying of La Cuevuca (site 177) which at Easter had been lengthened to 441m and deepened to 84m ending at a sump at the base of a 60m pitch. Cubio del la Reņada (48) was lengthened by 200m beyond the upstream sump although nothing of any real promise was found. Also in Reņada, Bootlace Passage met a section of the main stream; this find indicates a totally new direction for exploration as the river is heading into the hill away from the resurgence.

   Toad in the Hole (site 258) was entered after a two-day dig in a draughting shakehole - about 600m of large passage ended at a draughting choke. Situated at the far end of La Vega, in an area devoid of large caves, Toad has opened the batting for a big system which could exist here.

   However, the gem of La Vega turned out to be Torca de Coteron (site 264). Situated 900 m from Reņada entrance and 180 m above it, exploration began in the normal "it's bound to choke" manner. Paul Gelling on the first descent found himself dangling above a large chamber at the end of his rope; on his second drop he touched bottom and explored about 200m, after which he wrote in the log "... now needs surveying and photographing; also a good chance of the passage being pushed further... "

   Seventy six man-trips later, and with 3.5km of passage surveyed to a depth of about 200 m, the cave still has 8 undescended pits and many unexplored passages. One of the most impressive features of the cave is the entrance shaft itself. With dimensions at the top of 5m by 1.5m, and 45m deep, the gale that blows up waves about any loose clothing and also brings up a cloud of steam that is visible a hundred metres away. From the base of the shaft, the cave can be divided into 3 parts: the first is a phreatic ramp, initially on calcite and then boulders which eventually are at their angle of rest at the head of a 12m pitch into a large, descending, boulder-floored rift. The second stage starts just below here and is a major phreatic level about 140 m below the entrance. Parts of this level are extremely well decorated with calcite, while the floor in many parts is a mixture of sand, calcite, breccia, rounded sandstone cobbles and gypsum flowers. Progress through most of its 1.7 km length is by walking with the odd scramble through a blow-hole. The western arm branches - both end close to Renada - one arm being pushed down a series of pitches to a duck at the deepest point, the other being virtually unpushed. The eastern arm has at its end an unentered "stomper" at the head of an awkward climb.
    When Coteron is joined with Renada next year the length will immediately jump to over 10 km, and with its many unpushed leads and general direction, the Coteron-Renada System could become the longest in the area.

   Matienzo is now a way of life for a number of British cavers. We are still in the middle of the "Golden Age" with virtually every day of an expedition adding a new cave to the list. Many problems remain to be solved and there is still a large amount of enthusiasm left to solve them.

   Thanks for the success of this years expedition must go to Pete Smith, whose winter walks around the area locate many of the new holes; the Spanish caving authorities for permission to continue our exploration, and the Sports Council who, through NCA and the Ghar Parau Foundation, provided a substantial grant.

BCRA Transactions 8(2) was published June 1981. The 4 sections can be seen below.

Caves and Caving in Matienzo L. D. J. Mills
Geomorphology of the Matienzo Caves L. D. J. Mills & A. C. Waltham
Prehistoric Remains and Engravings discovered by the British Speleological Expeditions to Matienzo P. Smith
Matienzo Underground J. S. Corrin & P. Smith