Proceedings of the 12th International INQUA meeting on paleoseismology, active tectonic and archaeoseismology

R E F E R E N C E S Allemand, P., Brun, J.P., Davy, P., Van Den Driessche, J., 1989. Symétrie et asymétrie des rifts et mécanismes d'amincissement de la lithosphère . Bulletin de la Société Géologique de France 3, 445-451. Arias, L., 2019. La Formación las Chilcas en el valle del Estero los Ángeles (32°31’S), Chile central: Evolución sedimentaria y estratigráfica e implicancias paleogeográficas durante el cretácico. MSc Thesis (Unpublished), Departamento de Geología. Universidad de Chile, 244 pp. Balé, P., 1986. Tectonique caddomienne en Bretagne nord. Interaction décrochement chevauchement: champs de déformation et modélisations experimentales. These de 3eme cycles, Université de Rennes, 361 pp. Ballard, J.F., 1989. Approche géologique et mécanique des décollements daps la croûte supérieure. PhD Thesis, Université de Rennes I , 301 pp. Bonnet, C., Malavieille, J., Dominguez, S., Philip, H., 2004. Morphology and structure of active thrust fault surface ruptures: analogue modeling. Bollettino di Geofisica Teorica ed Applicata 45, 17–21 Buiter, S.J.H., Schreurs, G. (Eds.). 2006. Analogue and Numerical Modelling of Crustal-Scale Processes. Geological Society, London. Special Publication, London. Estay, J., 2019. Tectónica activa en el borde occidental de la Cordillera Principal de Chile central (29°- 36°S). MSc Thesis (Unpublished), Departamento de Geología, Universidad de Chile, 181 pp. Estay, J., Pinto, L., Easton, G., De Pascale, G. P., Troncoso, M., Carretier, S., Forman, S.L., 2023. Active thrust tectonics along the western slope of the Central Andes southernmost Pampean flat slab segment (33°S, Chile): the Cariño Botado fault system. Geomorphology 437, 108801. Hubbert, M. K. 1937. Theory of scaled models as applied to the study of geological structures. Geological Society of America Bulletin, 48, 1459–1519. Malavieille, J., 2010. Impact of erosion, sedimentation, and structural heritage on the structure and kinematics of orogenic wedges: Analog models and case studies. GSA Today 20 (1), 4-10. C O N C L U S I O N S The results of analog modeling indicate a significant influence of syntectonic sedimentation rate on the geometry of orogenic edge structural systems. Variations in angles, displacements, and height of the structural system suggest that exposure to higher rates of syntectonic sedimentation limits its ability to propagate toward the deformation front. The division between zones with different sedimentation rates interacts with the same structural system, allowing for comparing the structural system propagates over a greater distance in the zones with a lower sedimentary load than the other zone with a higher sedimentary load, resulting in a minor structural propagation. Applying analog modeling to the natural system of the PFZ, models successfully explain the difference in structural system propagation between the southern and northern zones, with greater propagation in the latter, where syntectonic sedimentation is the primary factor driving this difference. Furthermore, the westward emergence of the deformation front of the structural system north of the Los Andes-San Felipe Depression results from the lack of sediments hindering its propagation in that direction. A C K N O W L E D G M E N T S This study was mainly supported by the FONDECYT Project 1200871 (L. Pinto). We thank Camilo Pérez and Paula Montiel (University of Chile), who supported the modeling device's construction and the experiments' development.