Maar-type volcano, the artificial lake is partly nestled in a vast explosion crater whose edges you can guess. Access from the leisure centre. Hike to the suc de Lestrat (1 hour round trip, 1 km, 120 m drop, forest path).
Description
Between the Eysse and Escoutay valleys, the site of Saint Martial appears clearly below the eastern edge of the plateau, 5km east-northeast of Mont Gerbier de Jonc. With an area of 13 ha, the lake of Saint Martial occupies a depression dominated in the North East by the phonolitic volcano of Lestrat. Its outlet faces south towards the Escoutay valley, which the overflow waters reach via the short, steep-sided valley of Moulinou, a former water mill currently located below the dam. The village of Saint Martial which is reflected in the waters of the lake forms a growing balcony perched on the western flank of the depression.
The history of the lake is told by Paul Camus (1927).
According to the documents, it was probably between 1688 and 1738 that a natural outlet opened towards the Moulinou, which caused the lake to drain. Its site was then occupied by a marsh on which the culture gained little by little. In 1974 the construction of a dam above the Moulinou, led to the creation of the current artificial lake intended to diversify the tourist potential of the village.
Like the maar of Borée, the maar of Saint Martial is an explosion crater corresponding to volcanic activity of the phreatomagmatic type linked to the water-magma encounter. It is also recent, a few hundred thousand years at most (Vivarais volcanism).
The activity began with an effusive phase (lava outpourings without explosion) during which a basaltic flow was emitted towards the Escoutay valley. The dam caused by this flow blocked the watercourse and created a reservoir which must be at the origin of the transition to phreatomagmatic activity. The explosion crater is probably located at the location of the more or less circular depression currently occupied by Lake Saint-Martial.
The troglodyte caves of Cros Laplanche occupied until 1945 were dug by man in lahars (muddy flow) here very thick, the material offers the double advantage of being both soft and stable. There are also lahars downstream of the Escoutay valley as far as La Chazotte.
Products of the explosions: small quarries on the back of the southern slope of the crater, on the edge of the D215 (towards St Andéol de Fourchades, superposition of layers).
Opening
All year.
Access to Suc de Lestrat, picnic area, playground... Supervised swimming in July and August.
We also offer:
Quiet campsite located on the edge of Lake Saint Martial. Ideal for swimming, water games and fishing. Walks, near Mont Gerbier de Jonc, source of the Loire at 10 kms.
You want to recharge your batteries in an idyllic setting, this lake is made for you. Located at an altitude of 800 meters, surrounded by mountains, you can get some fresh air! Come and enjoy the lake with its nautical and leisure center.
Prices
| Free. |
Location