EXPERIMENTAL MODELING OF TECTONIC SEDIMEN TATION RELATIONSHIPS BETWEEN FORE-ARC BASIN AND ACCRETIONARY WEDGE

Analysis of sand-box models have been used to study the complex deform ation zone between accretionary wedge and forearc basin. Experiments s how that the evolution of the basin is controlled by a major backthrus t zone, induced by the velocity discontinuity localized near the tip o f the rigid backstop. The shortening is accommodated by the decollemen t spreading towards the toe of the wedge and the major backthrust zone . This steady state is driven by a mechanical balance between these 2 types of structures. The sedimentation in the forearc basin records th is interaction.