Aven d'Aurel n°1

From a narrow opening (0.4 m x 0.4 m according to Source n°2), the aven begins with a 17-metre shaft. A horizontal joint, 7 metres long, follows it and leads to a 15-metre shaft, followed by another 19-metre shaft breaking through the ceiling of a small gallery. This gallery, obstructed by calcite at one of its ends (salle du Renard), opens at the opposite end onto a new series of shafts: 10 metres, 8 metres, 12 metres and finally 22 metres clogged at the bottom with clay (elevation -99 metres). A climb of a few metres on the north-east wall allows access to a descending, unblocked forced conduit. It ends after a final vertical step at an ultimate clay fill, the current lowest point of the cavity (elevation -106 metres). At the base of the 8-metre shaft (elevation -66 metres), a very narrow vertical joint, about thirty metres deep, opens up.

The aven d'Aurel opens in the fine Bedoulian limestones, transition facies, with passage to the lower bioclastic facies with chert-bearing calcarenites, towards -50 metres. The aven was carved out at the expense of a system of joints with NE/SW and NW/SE orientations, which follow the line of the major fault bordering the left bank of the Sault basin and which passes 50 metres from the aven. On the other side of this fault are the undifferentiated Oligocene marls; it is these marls that are found in part at the bottom of the pit. Dip of the visible beds at -50 metres: 15° south.

One of the ends of the small gallery is obstructed by calcite (salle du Renard).

The very narrow vertical joint opened at the base of the 8-metre shaft (elevation -66 metres) carries a trickle of water.

A survey, of mediocre quality and reliability, dating from the 1960s, is visible in the 1970 BRGM report referenced 70-SGN-168-HYD, plate 3 (see: http://infoterre.brgm.fr/rapports/70-SGN-168-HYD.pdf - page 12/71 of the file).

Source(s): 1 - GAUBERT Gérard and LE FALHER Benoït, « Arcanes de Vaucluse - Hydrologie et spéléologie des territoires alimentant en eau la fontaine de Vaucluse TOME 2 », Association de Recherches et d'Etudes Hydrologiques du Plateau d'Albion (AREHPA), 1995, page 154. 2 - BRGM, Rapport 70 SGN 168 HYD, « Etude spéléologique du bassin d'alimentation présumé de la Fontaine de Vaucluse. », 1970, page 8 and plate 3: http://infoterre.brgm.fr/rapports/70-SGN-168-HYD.pdf. Source: GUILLEMIN G., 1975, « Blousons d'Argile », bulletin du Groupe spéléologique de Carpentras (GSC), n°6/7, pages 10-13.