Genesis and evolution of small-scale structures in the toe of the Barbados Ridge accretionary wedge

Abstract

Cores from Leg 110 document the development of small-scale structures generated both during the initial propagation of the basal decollement zone into the abyssal plane section and the subsequent thickening of the wedge. At the macroscopic accretionary front, sub-horizontal compressive stresses become localized in the off-scraped section rather than in the underthrust sediments. In contrast, strata associated with the basal decollement zone may experience layer parallel extension resulting from a combination of simple shear and possible flattening strains. The zone of intense scaly fabrics associated with the basal decollement and other thrusts appears to thicken with increasing displacement. -from Authors