Influence de la charge sedimentaire sur le developpement d'anticlinaux synsedimentaires; modelisation analogique et exemple de terrain (bordure sud du bassin de Jaca)

Growth folds on decollement levels are commonly observed in compressive basins. Relevant parametres for analogue modelling are provided by the N-S growth folds of the southern border of the Jaca basin (Spain, southwestern Pyrenees). The aim of this paper is to investigate whether sedimentation influences the evolution and shape of growth folds. A comparison between analogue models and field structures suggests that: (1) the shape of folds depend on sedimentation rate; when this rate increases, fold growth is hindered; (2) fold assymetry is favoured by localized sedimentation; (3) the cessation in growth of an anticline may be the result of an increase in sedimentary supply.