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Cependant, cet espace de liberté n'a pas vocation à défouler ceux qui
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les messages polémiques ou d'insultes seront modérés.

Merci pour votre contribution cordiale et constructive.

Auteur Titre: Bestouan, galerie du Flou par John Volanthen Date
Frank Le Bestouan, Cassis France
Divers: Al Wallace, John Volanthen
28 & 29 May 2005

After a number of failed attempts to reach the end of the Bestouan during September and October, mainly due to the weather, It was decided to change the time of year completely in an attempt to find the sea calm for a suitable period. On the 28th May, in glorious weather I staged a scooter and line reel just beyond the 1400m air bell, noting the flow to be somewhat less than previous attempts, this dive lasting just under 90 minutes was very quick and enjoyable.

On the 29th, I re-entered the cave, and reached the staged scooter uneventfully. Proceeding on into the cave, the junction leading to the gallery du Flou was reached in good visibility. The junction was obvious due to the mixing zone encountered downstream. The Galerie du Flou line lead off up and to the right. All line repairs made to this point by Rick Stanton and myself in preceding years had survived intact, allowing quick progress to this point.

The tunnel leading to the Gallery du Flou was easily visible high on the right, but seemed to head back in the downstream direction. After stirring some silt to check it was really going upstream I set off again, but in much smaller passage. One line repair had to be made before I was able to surface in the Gallery du Flou. This is much smaller than the cave diagram indicates, being only about 3m long.

Continuing on, the passage undulated much more than expected, before reaching -31m (the deepest point in the cave). After more undulations, the end of Marc Douchet's line was reached at 3000m on the right hand side of a large debris slope which blocked the passage. The line ended where the passage roof dipped to meet the rising slope. I parked my scooter here and examined the choke point, finding a slight arch in the roof off to the left. By moving some of the boulders I was able to see through to open passage and find that the unstable looking slope continued upwards, with the passage opening out again. Moving more boulders, the diver carefully squeezed through into open passage and followed the slope to surface, laying 25m of line.

The rubble slope continued to meet the roof on the right, with the bulk of water issuing around a large boulder on the left and through the slope, leaving a 20cm high gap between roof and floor. 20 minutes were spent moving boulders, in an attempt to enlarge the hole to allow a diver to pass, however without removing equipment it was impossible to squeeze through.

The speed of the water and the looseness of the boulders both above and below water dissuaded me from removing equipment, however 10m of air bell can be seen beyond, with the passage disappearing round a right hand bend. The return through the boulder choke squeeze was problematic due to the volume of silt disturbed by digging in the new chamber. Once I was able to get ahead of the silt cloud, the return trip became easier. It is likely that once the top of the debris slope is passed, open passage will continue. Total dive time 4.5 hours, A return is planned soon.

Equipment used:

Ø 1 modified inspiration
Ø 1x Joki
Ø 1x 18L cylinder NX 36
Ø 1x UV 38
Ø 1x UV 26
2005-06-07 22:37:27
John V

Le Bestouan, Cassis France
Diver: John Volanthen
22/10/05

Returning to the Bestouan I intended to re-examine the choke and hole at the end. I decided not to stage equipment this time to make the best use of a marginal single day weather window. Leaving one scooter at 1300m I proceeded to the end of the cave and re-examined the hole found in May. The water was higher this time, with the hole being completely submerged, however after moving more boulders I was able to de-kit and drag through one rebreather and one cylinder and surface on the far side in another air bell. A small boulder ramp led off forwards for 20m but the airbell closed down. The way on was underwater, under the left wall.

Continuing on, leaving the breakdown area, the passage unexpectedly surfaced within 30m in a large 35m high chamber, completely blocked with a boulder slope and small infill. I climbed this slope to the top of the chamber and examined the chamber walls but no way on could be found. The water flows through the slope, emerging from gaps in the boulders. On the way back, a bypass was found to the squeeze allowing equipment to be kept on. no return is planned.
2005-10-24 13:59:23
Xavier Méniscus Congratulation John !
Content de t'avoir donner un coup de main.

Pour y avoir été déplacer quelques blocs, il y a 15 jours, c'est une plongée super sympa.

J'ai compris pourquoi Marc avait nommé cette galerie "la galerie du flou", parce qu'au carrefour, l'eau est vraiment trouble, par le taux de salinité différent entre les 2 galeries
Par évident d'avoir trouvé le départ de la galerie dans ces conditions.

Et dans la trémie, au fond, ça touille pas mal au retour, par les blocs que l'on déplace, et l'étroitesse des lieux



A+
Xavier
2005-10-24 14:35:40

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