Identification of Ordovician block-tilting in the Hercynian fold-belt of Central Brittany (France): field evidence and computer models - Brun, Jean-Pierre; Ballard, Jean-François; Le Corre, Claude (J. Struct. Geol., 1991)
The significance of the Brioverian-Lower Ordovician unconformity in Central Brittany has been discussed by many authors. A new interpretation in terms of extensional tectonics is presented, based on structural, sedimentological and stratigraphical data. However, because sedimentary formations have been strongly folded by Hercynian deformation, extensional structures are obscured and difficult to recognize. To identify the normal faults, the geological map is compared with computer models of the folded tilted blocks. It is shown that major normal faults had a mean N70° trend, dipping toward the SE with an almost regular spacing of 7-8 km.
Keywords: journalArticle; Géologie