Évent d'Alibert n°1

The entrance measures 0.5 m x 1 m and was cleared by the CLPA. It leads to a narrow 5-metre pit, followed by a narrow passage towards the west then south-southeast, generally sumping. One emerges into a gallery 3 m x 2 m and 29 metres in development, oriented west-southwest. At its terminus, one can continue southwest for 31 metres in a forced conduit 1 m x 1 m blocked by concretion at the bottom. At the start of this crawlway, a north-oriented flat-out sump is observed. A narrow network, cut by semi-sumping pools or sumps, leads to a gallery 2 m x 1 m and 59 metres long, which ends in a sump and begins with a lateral blowing hole (flat-out crawl in liquid mud).

The forced conduit of 1 m x 1 m is blocked by concretion at the bottom.

The narrow passage following the pit is generally sumping. The narrow network is cut by semi-sumping pools or sumps, and the gallery of 2 m x 1 m ends in a sump; its start is a lateral blowing hole, flat-out crawl in liquid mud.

The north-oriented flat-out sump can be bypassed by a series of scabrous narrowings; the sumps of the narrow network can be bypassed by gruelling narrowings.

Geology: dolomitic Bathonian.

Source: Groupe d'études et de recherches spéléologiques et archéologiques de Montpellier (GERSAM), « L'Inventaire du Larzac et de la Séranne » > 5. COMMUNE DU CAUSSE DE LA SELLE (HERAULT) > 5.2 - Évent d'Alibert n°1: https://www.jfbrun.eu/gersam/causse.htm