The Velardeña District is located on the eastern flank of the Sierra Madre Occidental mineral belt, on the boundary between the Sierra Madre and the Mesa Central metallogenic provinces. Most of Mexico's high-grade silver mines are located in the Mesa Central province, near this contact.
The regional geology is characterized by a thick sequence of limestones and minor calcareous clastic sediments of Cretaceous age, intruded by Tertiary plutons of acid to intermediate composition. During the Laramide Orogeny, the sediments were folded into symmetrical anticlines and synclines that were modified into a series of asymmetrical overturned folds by a later stage of compression. This event also buckled the stratigraphy about a northeast striking, vertically dipping hinge-line around the village of Velardeña.
A series of felsic to intermediate intrusive rocks occurs over a strike length of approximately 15 kilometres, possibly located along the hinge-line mentioned above. Local development of exoskarn, endoskarn, hornfels and marble occur associated with the intrusives. The mineralization at the Santa Maria Mine in Velardeña and all of the various workings on and around the property occurs along this trend and is spatially associated with the intrusives and related alteration.