Boulou (river)

from Wikipedia, the free encyclopedia
Boulou
The Boulou at Moulin de Fontas shortly before its confluence with the Dronne

The Boulou at Moulin de Fontas shortly before its confluence with the Dronne

Data
Water code FR :  P7110500
location France , Nouvelle-Aquitaine region
River system Dordogne
Drain over Dronne  → Isle  → Dordogne
source in the municipality of Sceau-Saint-Angel
45 ° 27 ′ 47 ″  N , 0 ° 40 ′ 45 ″  E
Source height approx.  195  m
muzzle on the municipal boundary of Bourdeilles and Creyssac in the Dronne Coordinates: 45 ° 19 ′ 8 ″  N , 0 ° 33 ′ 43 ″  E 45 ° 19 ′ 8 ″  N , 0 ° 33 ′ 43 ″  E
Mouth height approx.  86  m
Height difference approx. 109 m
Bottom slope approx. 4.5 ‰
length 24 km
Left tributaries Pré Pinson or Belaygue
Right tributaries Jallieu
The Boulou at Les Quatre Fonts, the municipal boundary of Paussac-et-Saint-Vivien and Bourdeilles

The Boulou at Les Quatre Fonts , the municipal boundary of Paussac-et-Saint-Vivien and Bourdeilles

The Boulou , Bolon in Occitan , is a small river in France that runs in the northern part of the Dordogne department ( Nouvelle-Aquitaine region ). It rises in the municipality of Sceau-Saint-Angel , in the Périgord-Limousin Regional Nature Park and flows into the Dronne as a right tributary after 24 kilometers at the municipal boundary of Bourdeilles and Creyssac . Its average gradient is 4.56 m / km.

Flow through communities

In the canton of Périgord Vert Nontronnais :

In the canton of Brantôme :

course

The Boulou rises not far south of the church of Saint-Angel (municipality of Sceau-Saint-Angel) at an altitude of about 195 meters. Until shortly before the hamlet of Puygombert (municipality of Léguillac-de-Cercles) it flows more or less in a south-westerly direction for almost 14 kilometers, before taking a south course, which it maintains as a right branch into the Dronne until its confluence. The height of the mouth of the Boulou is 86 meters and the river has then flowed through a total of 23.9 kilometers. Behind Le Marquisat (municipality of La Gonterie-Boulouneix) it takes up the Jallieu as its right tributary ; below La Verrerie (municipality of Paussac-et-Saint-Vivien), the Belaygue (or Pré Pinson ) comes towards it as a left branch . With the exception of the municipality of La Chapelle-Montmoreau, the upper reaches of the Boulous are located in the Périgord-Limousin Regional Nature Park .

geology

In its upper reaches, the Boulou flows through flat layers from the Upper Cretaceous , which belong to the Combiers-Saint-Crépin-de-Richemont syncline (northern Aquitaine basin ). The headwaters are still in Limestone des Ligériens ( Unterturon ). Shortly before the center of La Chapelle-Montmoreau, the Boulou then enters more resistant areas of Angoumiens (Oberturon). Fossil limestone of the Coniacium (up to the hamlet of Les Brageaux ), then typical chalk limestone of the Santonium (around Saint-Crépin-de-Richemont) and at La Forge even Untercampan follow . Here the Boulou then crosses an east-southeast trending fault zone , the Mareuil Fault . As a result, the river meets Angoumien again, from Puygombert then Coniacium. These two layer sequences already belong to the Gout-Rossignol-Léguillac syncline ; they too are more or less flat. From Les Quatre Fonts (municipality of Saint-Julien-de-Bourdeilles), the influence of the La Tour Blanche anticline becomes noticeable and stratigraphically deeper angoumia appears again. Further south, the river then crosses Ligérien and, in the center of the anticline, even briefly cenomanium (near Les Farges , municipality of Paussac-et-Saint-Vivien). In the last few kilometers, the valley narrows, the Boulou cuts through Ligérien and then encounters resistant Angoumien (popular climbing rock) that forms steep walls and accompanies it to the confluence with the Dronne.

ecology

European mink Mustela lutreola

The Boulou with its wetlands forms an important regional ecotope , which was designated as ZNIEFF ( French zone naturelle d'interêt écologique, faunistique et floristique ). There are also plans to put the river under Natura 2000 protection. In addition to numerous wild plants and 361 different types of butterflies , the mink ( Mustela lutreola ) , which has now become very rare, and the otter ( Lutra lutra ) can also be found here .

history

The human presence in the Bouloutal can be traced back to the Moustérien ( Abris at La Tabaterie - Abri Sendouge or Abri Sondougne and Abri Brouillaud ). In the second Iron Age between 600 and 500 BC There was an oppidum on Roc Plat . Remains from Roman times have been discovered in the Boulouneix cemetery . With the emergence of the early medieval village structures around the year 1000, numerous Romanesque churches and a priory were built .

Landmarks on the river

Individual evidence

  1. ↑ a b geoportail.fr (1: 16,000)
  2. ↑ a b The information on the length of the river is based on the information about the Boulou at SANDRE (French), accessed on December 24, 2010, rounded to full kilometers.

literature

  • Floc'h, J.-P. et al .: Feuille Nontron . In: Carte géologique de la France at 1/50 000 . BRGM.
  • Platel, J.-P. et al .: Feuille Périgueux (Ouest) . In: Carte géologique de la France at 1/50 000 . BRGM.