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The La Tour-Blanche Anticline, also called Chapdeuil Anticline or Chapdeuil-La Tour-Blanche Anticline, is a tectonically caused, dome-like upwarp in the sedimentary succession of the northeastern Aquitaine Basin in France. The structure is oriented westnorthwest-eastsoutheast. == Description of the structure == The anticline was named after La Tour-Blanche, a small town in the northwestern Dordogne. Yet the centre of the structure is situated farther southeast within the commune of Chapdeuil, hence the names Chapdeuil Anticline or Chapdeuil-La Tour-Blanche Anticline. In plan view the structure has the shape of a nearly rectangular parallelogram with the base lines striking ESE-WNW (N 120) and the sides more or less N-S (reference horizon being the Ligérian/Angoumian boundary). In its long dimension, the anticline measures about 6 km, yet across strike merely 3 km. Similar in shape to the Mareuil Anticline, the La Tour-Blanche Anticline has an asymmetric profile with a steeper northeastern flank (dipping 20° to the NNE) and a very gentle southwestern flank (dipping 5° to the SSW). The northeastern flank is accompanied by a reverse fault with very little heave (10–15 m). On its northern side, the La Tour-Blanche Anticline yields to the ''Villebois-Lavalette-La Chapelle-Montabourlet Syncline'' (also called ''Gout-Rossignol-Léguillac Syncline''). After a pronounced structural flexure, traceable from Verteillac to Grand-Brassac, follows to the south another syncline (northeast of Ribérac) entirely composed of Campanian strata at the surface. The next anticlinal high traverses Montmoreau in the Charente department and ends just northwest of Ribérac. The eastern end of the La Tour-Blanche Anticline is crossed by several normal faults trending mainly NE-SW. East of Saint-Just the axis of the anticline slowly disappears simultaneously changing its direction to an easterly course. The structure then definitely ends on the east side of the Boulou (near Paussac). The area of the anticline is drained in a southeasterly direction by the Euche river, a right-hand tributary of the Dronne, and by the Buffebale, a small rivulet and left-hand tributary of the Euche. It demonstrates inverted topography, i.e. the core of the structure is a depression. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「La Tour-Blanche Anticline」の詳細全文を読む スポンサード リンク
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