The control of pre-existing extensional structures on the evolution of the southern sector of the Aconcagua fold and thrust belt, southern Andes

摘要: Abstract The Aconcagua fold and thrust belt, located in the Andean mountains at 32°30′ to 34°S, has been described as a classic model of thin-skinned belt. However, new structural data from its southern sector have shown that it complex framework reflected multiple Mesozoic extensional phases, overprinted by inversion, well thin- thick-skinned tectonics. Two major superimposed styles identified for characterized distinctly oriented stress fields. A key role evolution this part belt was played Late Triassic Early Jurassic depocentre block faulting. Shortening accommodated combination inversion pre-existing normal faults, development footwall short cuts both thin thrusting. Synrift postrift sedimentary rocks were uplifted reactivation with further shortening along newly formed faults. geometry fault systems is controlled architecture rift basin, competent footwalls forming barriers lateral propagation detachments.