Matienzo 1983
A summary of the cave explorations which occurred in Matienzo during 1983
With over 6km found this summer, people might be excused in thinking
that finding cave passage in Matienzo was as easy as ever. Not so - half
of this years length of tunnel was discovered by 'pushing' at the end of
known systems; 6 days digging was necessary to enter one extension and
the second was gained after 7km of tedious caving.
The expedition started quietly enough with a small team investigating
numerous small, choked shafts on the northern side of the Vega valley.
(SRT fans might be interested to know that ladders were used for every
one - and not a single bolt). Attention shifted to the other side of the
valley, above the South Vega system, where 200m was surveyed in site 37,
Cabritilla (and a strongly draughting dig abandoned after hitting solid
rock); Squirrel Wood finally (after 10 years of chiselling) slipped through
the windy entrance of 'ammered 'ole (457) finding the inevitable choke
25m down; and on Pat Devines birthday, Sima Cumpleaños (459) was
bottomed. Fairly typical of the small finds, a 5m pitch dropped onto rubble
with a tight continuation down to a mud floor 13m below. A short series
of joint aligned, 1m diameter tubes entered a rift containing an 8m sloping
pitch to a 1Om long chamber. By this time, most of the team thought 'We've
cracked it!', but 10 minutes later all leads were found to choke. Length
of this one was 120m, depth 35m.
Attention switched to bigger things on the southern side of Vega and Torca
de Coteron (site 264) was tackled up to continue looking at the many leads.
Effort was concentrated on pushing to the west over the upstream sump in
Reñada and to the east where a blank mass of limestone needs 'filling
in'. The western front was advanced very little; all attempts met with
boulders and the only ways appeared to be up or down among them. One passage
that did appear to go in solid rock only bent round and dropped back to
the start. (At one point in this route both walls of the rift consisted
of one foot diameter limestone 'lenses'; the climb up to a higher level
continuation necessitated forceful bridging manoevres just to keep the
lumps in place). On the eastern front, Bootlace Passage was attacked at
a short climb and Battery Passage immediately entered. With an initial
strong draught, Battery Passage passes through low crawls, vadose and phreatic
passage and 'ends' at chokes or tight sections. Passage direction' is generally
north and it almost joins with Matutano Passage, discovered at Easter;
length is 0.5km and pushing prospects are excellent.
In Reñada below, the western side of the trade route was extensively
poked into but little progress was made; Sanatogen Passage, heading SW,
was re-explored and again little progress made.
High up on the same hillside, to the east of the South Vega System, site
472 (a newly discovered open entrance) was bottomed at 135m. A central
deep shaft has various levels running off on the way down which require
pendulum tactics to enter. All ways choke.
The entrance to Cueva Uzueka (107) lies in Riaño and its maze like
entrance series leads into a streamway which heads generally south east
and then east towards Llueva and its eventual resurgence in Secadura. It
is along the early section of this easterly passage (Rocky Horror) and
beyond, that the cave comes close to the main sink in the Matienzo depression
and over the years many attemps have been made to dig out draughting holes
on the hillside above the disappearing water at Carcaveuso (site 81). This
year saw the end of Uzueka extended by 2.2km and much excitement and speculation
when the passages headed for the surface in Matienzo.
It was a couple of years ago that John Thorp, on a trip to the end of Uzueka
(trying to follow the water between the boulders) clambered up a steep
calcite slope on the right of Rocky Horror and came across a 'black hole'
which was assumed (with his ailing carbide), to be a pitch down. The first
team to reach the spot this year left ladder and rope behind as the drop
turned out to be a short clamber down over boulders into a large passage
ending at a 31m diameter chamber, 40m above the water and subsequently
named 'Camp 1' (no stops as yet). A walking-sized tunnel set off from this
and after a couple of climbs the stooping Mace Head Passage was reached.
Possibly the best decorated passage Uzueka, this 1m phreatic tube has a
profusion of calcite formations with large spikey crystals on the floor.
After 200m the way on enlarges and things then start to get out of hand.
A 15m high passage leads off into the distance with tubes going off on
the sides. After a number of 15 hour trips survey detail shows the Trident
Series ending at three points under the Carcaveuso hillside between 30
and SOm above the water and at an aven about 5Om below the ground level.
Two areas around the Matienzo depression have, in the past, failed to yield
any large lengths of cave passage. The larger and most difficult to prospect
is Muela, which rises to 700m above valley bottom, and the other is the
north side of the Vega valley. Some shaft bashing was done on Muela this
year - a couple of about 1OOm depth being the most significant - but the
best discovery was found in the second area by extending a pot found in
1978.
Since its discovery Dave Howard had been wanting to return to the end of
Mostajo (site 71) to scale onto a slope and then up to the roof, 9Oft above.
This year, Dave, pole, people and enthusiasm came together to attempt the
climb. Piers lead the assault, 25ft up leaving the pole behind and clambering
on slippery cal-ite up to the roof; a short crawl to the right along the
wall met a sandy ledge and a passage with the draught whistling out. After
a short distance the sandy floor required digging and half an hour later
the team were through and admiring 5ft straws and 18" helictites in
a passage some lOm wide. The next day saw a short climb tackled and a protracted
dig started some 400m from the entrance. The flat out digging was awkward,
not particularly because the floor halfway in was calcite, but because
the draught blew sand in the excavators' eyes. On the sixth day of digging,
the breakthrough was made. Nicely decorated at its start the passage enlarged
to 7m square with much gypsum on the floor and passed numerous pits in
the floor until 330m from the squeezes, a hole in the floor about 5Oft
deep stopped safe progress.
The following day, a traverse and climb around and up the sandy walls of
the pit gained the continuation, about 350m of similar passage, ending
in a boulder floored chamber but with an inviting rift in the roof lOm
above.
Although of no great length at 1300m, Mostajo has carved through the ridge
of Enaso and opened up an area which was previously barren of lengthy passage.
Incentives to return include undescended pitches off to the side of the
main way - routes that could meet a level of development 1OOm below, or
indeed the present 'water table' at 15Om depth.
Cave site numbers have risen from 427 to over 500 during this years explorations,
and although none of the caves explored are of great depth or length (Uzueka
at 15.65km is the 5th longest in Spain, Coteron the 6th), the series of
expeditions over the last 13 or so years have certainly been the most persistant
to leave Britain, gradually unearthing the remarkable number and variety
of caves around Matienzo.
As usual our thanks must go to the Char Parau Committee for administering
the Sports Council Grant and to the Spanish Authorities for their willingness
in allowing us to continue with our explorations. Also in Spain, Juan Carlos
Gutierrez has actively encouraged our work with much discussion and Pete
Smith has been the instigator of much discovery by wandering over the area
during the winter months. Bob Machin kindly lent a Molephone set to the
expedition which was put to good use in the Uzueka extensions.
amended from an original article by Juan Corrin in Caves
& Caving 22.