Échelle (river)
| Échelle | ||
 The Échelle at the foot of the hamlet of Roches near Sers |
||
| Data | ||
| Water code | FR : R2320500 | |
| location | France , Nouvelle-Aquitaine region | |
| River system | Charente | |
| Drain over | Touvre → Charente → Atlantic Ocean | |
| source | in the municipality of Dignac 45 ° 32 ′ 41 ″ N , 0 ° 16 ′ 23 ″ E |
|
| Source height | approx. 185 m | |
| muzzle | at Sources de la Touvre in the Touvre coordinates: 45 ° 39 ′ 43 " N , 0 ° 15 ′ 23" E 45 ° 39 ′ 43 " N , 0 ° 15 ′ 23" E |
|
| Mouth height | approx. 48 m | |
| Height difference | approx. 137 m | |
| Bottom slope | approx. 8.1 ‰ | |
| length | approx. 17 km | |
| Catchment area | 68 km² | |
| Left tributaries | Ruisseau de Bellevau, Ruisseau de Rochejoubert, Lèche | |
| Right tributaries | Ruisseau de Beaulieu, Ruisseau de Cloulas | |
The Échelle is a river in southwest France that runs in the Nouvelle-Aquitaine region . It rises in the municipality of Dignac about 1 kilometer south of the town center and flows after about 17 kilometers at Font de Lussac as a tributary into the Touvre . Their average gradient is 8.56 m / km.
etymology
Contrary to expectations, the name Échelle does not derive from the French échelle (ladder), but has its origin in the La Lèche river in the municipality of Touvre (or in the district of the same name in the municipality of Touvre). L'Échelle is thus the diminutive of Lèche - Lèch • elle - and then means little Lèche .
Crossed departments
- Charente , in the Nouvelle-Aquitaine region
Places on the river
- in the canton of Boëme-Échelle :
- in the canton of Touvre-et-Braconne :
Hydrography
The catchment area of the Échelle is 68 square kilometers with a height difference of 137 meters. Left tributaries are the short Ruisseau de Bellevau in the municipality of Sers, the 2.3 kilometer long Ruisseau de Rochejoubert , which flows through the municipalities of Garat , Magnac-sur-Touvre and Touvre, and the very short Lèche immediately south of the confluence with the Touvre . Right tributaries are the Ruisseau de Cloulas and the Ruisseau de Beaulieu in the municipality of Dignac. The latter in turn takes on the Ruisseau de Charbontière and the Ruisseau du Roc on the right. Other side valleys less than 1 kilometer long flow at Roches (on the right) and at Roprie (on the left).
A sewage treatment plant is located at Dignac, a water quality observation post below the hamlet of Peusec (Garat municipality) and a hydrometric measuring station is installed in Touvre.
geography
The Échelle rises at 185 meters above sea level in the hamlet of La Marronnière (municipality of Dignac) in the Forêt de Dirac . It initially flows in a north-easterly direction, but then turns in the municipality of Sers to the north-north-west, to flow into the Touvre at 48 meters above sea level.
geology
The source of the Échelle is located in a continental detritus that is no more than 20 meters thick and originates from the further east basement of the Massif Central . These are clayey sands interspersed with gravel , the age of which is classified as Miocene / Pliocene . Not far further north, near Dignac, the river reaches down to underlying, flat-lying upper chalk sediments of the northern Aquitaine Basin . First of all, 30 meters thick sub- canton consisting of limestone containing glauconite is encountered, and then from Dignac 30 to 35 meters thick coniacium - limestone sands and hard fossil limestone. About 1 kilometer north-northeast of Dignac, the river cuts for the first time into 40 to 54 meter thick sediments of the Oberturon ( Angoumia ). After the confluence with the Ruisseau de Beaulieu on the right and the Ruisseau du Roc , where the Upper Paleolithic site of Roc-de-Sers is located on the right , the river enters the 30-meter-mighty Unterturon ( Ligérien ) after changing direction . From Moulin du Fourneau onwards , the 40 to 42 meter thick sediments of the Cenomanium are encountered - platy limestone, sands and clays - which transgressed over the Upper Jurassic and initiated the Upper Cretaceous Cycle. From Le Picard onwards , the Upper Jura is on the right side of the valley for the first time. The Upper Jurassic is built up from a good 130 meters of Oxfordium and 310 meters of Kimmeridgium . Immediately after crossing the D 4 from Marthon to Angoulême , the north-northwest-trending Échelle fault appears for the first time on the left side of the valley . The marl-rich Kimmeridgium east of the fault has been raised against the Cenoman in the west. The Oxfordium on the right side of the valley falls flat to the southwest at around 5 degrees.
A decisive facies change runs through the valley of the Échelle, affecting the sedimentary sequences of the Oxfordian and Kimmeridgian. Both episodes appear on the east side of the river valley in reef facies with bioclastic, partly gravelly reef rubble limestone, but in the west as clay limestone and marl . The marl facies are waterproof and therefore, in conjunction with the Échelle fault, causes the karst waters to rise in the springs of the Touvre and the Lèche.
The Échelle Fault is of regional importance and forms the southern continuation of the Touvre Graben , which extends to the Charente . It may also be connected to the laterally offset bandiat trench .
The valleys of the Échelle are filled with quaternary alluvium .
Due to karstification , the river loses water that reappears in the karst springs of the Touvre.
Landmarks on the river
- Roc-de-Sers - Upper Paleolithic site
- Fontaine miraculeuse ("miraculous spring") near Bellevau (municipality of Sers) with monolithic chapel and hermitage from the 6th century.
- The parish church of Saint-Cybard in Dignac from the 12th and 15th centuries.
- The Logis de Nanteuil castle in Sers from the 15th century.
- The Romanesque parish church of Saint-Pierre-aux-Liens in Garat from the end of the 12th century.
See also
- Charente
- Forêt de Bois Blanc (Charente)
- Forêt de Dirac
- Forêt d'Horte
- Karst of La Rochefoucauld
- Roc-de-Sers
- Touvre
