The Monterrey Salient formed as a result of uplift in the Mesa Central of Mexico and consequent gravitational sliding of the detached cover to the northeast during the Laramide orogeny. The salient is located south of Monterrey where the Sierra Madre Oriental orogenic belt arcs abruptly from an east-west to a north-south direction. It is composed of a series of arced, doubly plunging, en echelon anticlines, most of which are overturned to the north. Exposed in the area are Upper Jurassic carbonates and terrigenous rocks, and Lower Cretaceous carbonates. The salient also contains a few outcrops of Upper Jurassic evaporites which have flowed to the surface along fault planes. These evaporites, recognized as the Minas Viejas Group, are believed to be the decollement above wh ch the deformation occurred.

A crustal shortening of 50% is calculated in the Monterrey Salient. Most of the shortening is attributed to folding, in as much as surprisingly few major thrust faults have been observed. Field work also demonstrates that structural trends are directly related to buttressing effects of paleohighs and thick sedimentary basins. On the basis of these structural trends and recent stratigraphic studies, the Mesozoic Coahuila peninsula is found to extend in the subsurface farther to the south than has previously been assumed.

Both the stratigraphy and structural style make the Monterrey Salient a classic example of a gravity-induced orogenic belt.

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