Font del Truffe

The first submerged conduit opens at the bottom of the pool, whose level variations can reach 4 m. It begins with a narrow passage formed by two large blocks resting on the pebbles. At the base of the scree, the conduit widens and develops at -8 m up to 77 m from the entrance, where a shaft leads to -15 m and in which sand is noted. The floor then rises slowly, with small potholes in places, up to a fissure that opens into a dry chamber of 3 x 3 m.

The second sump, with a smaller cross-section than the first, is also more uneven and more corroded. Sandy deposits are noticeable at the base of the 2 shafts that lead to -15 m. Its development is 160 m and a dry gallery 17 m long follows it. Its small cross-section and very corroded floor make progression delicate.

The third sump plunges very rapidly to a depth of -15 m. Shorter than the previous ones (85 m), it leads to a gallery with rare speleothems. Two very narrow upper levels depart from the ceiling.

The fourth sump, with a sometimes modest cross-section (0.80 x 1 m), develops at a depth not exceeding 7 m over a length of 118 m.

At point 922, the access gallery opens into a chamber cluttered with blocks and clay, from which two galleries with abundant clay fill depart. These two galleries, of large cross-section (4 m wide on average for 3 to 4 m in height), appear in fact to be one and the same gallery.

The gallery following the third sump has rare speleothems.

The second sump begins immediately after the first, except at low water when 40 m of dry galleries must be traversed before reaching it; in that case, the level of the 2 sumps is not identical, the first dropping more rapidly than the second, then the 2 sumps subsequently stabilize at the same level. Unlike the first three, the level of the fourth sump appears to remain invariable.

In the dry galleries beyond the fourth sump, from point 684 to point 922, a free flow is detected whose discharge on 17/1/76 was approximately 5 l/s. The first part of the network thus appears as an underflow of the stream that once followed this now fossil gallery. This second part ends at each extremity with a sump.

The dry galleries beyond the fourth sump present, from point 684 to point 922, the same appearance as the other emerged parts. Three lateral galleries have been explored over about thirty meters.