Tectonic transpression in the Sierra Madre Oriental, northeastern Mexico: An alternative model

Visual analysis of the Shuttle Imaging Radar (SIR-A) of northeastern Mexico reveals the existence of several geologic features including (1) a well-developed pattern of en echelon folds, (2) juxtaposition of tectostratigraphic domains, (3) fold structures varying from fan-shaped, asymmetric to recumbent, doubly plunging anticlines, (4) anticlinal-synclinal trends associated with regional plunging and tilting of the structures, and (5) strike-slip faults oblique to the fold trends. These structures are interpreted as the result of late Tertiary transpressional stress related to a complex, anastomosed wrench-faulting system in the basement reactivated several times since the Late Jurassic. This transpressional orogenic belt in northeastern Mexico is linked to the spreading phase in the Gulf of Mexico.