Structural development of the Peregrina-Huizachal anticlinorium, Mexico

The Sierra Madre Oriental fold belt is a NW-SE-trending contractional belt that spans nearly the entire length of Mexico. This area underwent Triassic-Middle Jurassic rifting and Late Cretaceous-Early Cenozoic shortening. Our structural investigation of the Peregrina-Huizachal anticlinorium in east central Mexico shows that its development is characterized by two phases of deformation: an early thin-skinned phase and a late thick-skinned phase. A detachment developed at the contact between the rift sedimentary rock and overlying limestone. During the thin-skinned phase, deformation of the Upper Jurassic-Cretaceous strata is accommodated by a series of detachment folds and faults. The rift boundary faults are sub-perpendicular to the late stage compression in east central Mexico. This makes rift-related faults prone to be inverted as reverse faults. During the thick-skinned phase, the basement in the rift is uplifted along two opposing reverse faults and experience internal deformation. Its uplift contributed to the growth of the Peregrina-Huizachal anticlinorium. (C) 2006 Elsevier Ltd. All rights reserved.