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The Andean foreland of central-western Argentina (30°-35°S) is characterized by the interaction of the east-vergent, thick-skinned Sierras Pampeanas and the west-vergent, thin-skinned Precordillera. Blind thrust faults are associated with the transition between these structural provinces, and large earthquakes have resulted from their interplay beneath the cities of Mendoza and San Juan. This study develops and applies a geomorphic approach to reveal buried tectonic features at both the scale of individual structures and the regional-scale. We interpret changes in bank heights and sinuosity from three rivers located between the Cerro Salinas and Montecito anticlines to suggest the existence of a third, buried structure. Inflections in elevation swaths indicate these three structures may be connected by the southern continuation of the Cerro Salinas thrust, which would tie the three to the Sierras Pampeanas structural province. Regional-scale drainage in the Andean foreland shows that neither current- nor paleorivers have flowed across the Alto del Desaguadero area. Inflections in W-E and N-S elevation swaths across this area suggest the influence of tectonic forcing, possibly due to a rising basement structure similar to the Sierra Pie de Palo to the north.