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.