Fracture distribution in a folded fluvial succession: the Puig-reig anticline (South-eastern Pyrenees)

摘要: Sedimentary rocks of foreland fold-and-thrust belts typically undergo intensive fracturing as fold grows. The resulting fracture networks can present significant variations depending on the distribution sedimentary facies and complex structural characteristics belts. Puig-reig anticline, located in south-eastern Pyrenees, mainly exposes proximal fluvial deposits north limb medial rest anticline. Thus, this anticline constitutes an excellent case study to investigate main controls folded deposits, terms position lithofacies variations. Outcrops were selected be representative different positions, from hinge its limbs, a variety lithofacies, deposits. Fracture data acquired using linear scanline method. Results indicate that is affected by four sets fractures. dominated thick conglomerate bodies with interlayered sandstones deposited unconfined flash floods wide-shallow channel streams fan, presents large spacing low intensity but relatively length aperture. crest crest-limb transition zones are composed conglomerates, sandstones, siltstones clays, braided overbanks fan fractures high variable south limb, filling sandstone layers stable overbank fine characterised small Based multiple regression analysis, controlled position, bedding thickness lithological associations, more intense thin interlayers crest. associations. apertures higher affecting bodies. results relevant for characterising similar systems subsurface, where scarce.