Characteristics of the major epithermal gold deposits in the northern Sierra Madre Occidental, Mexico.

摘要

The nine largest epithermal gold systems discovered so far in the northern Sierra Madre Occidental (SMO) were analyzed and compared in order to find their similarities, which are potentially influential in the development of these major epithermal systems. Regional- and local-scale factors were considered.; Features such as related rocks, local structural setting, regional structures, stratigraphic location, and volcanic activity are the controlling factors that combined allowed the emplacement of major epithermal systems within the study area. Other factors, such as host rocks, density and type of structures, are responsible for the shape of the ore bodies. Additionally, low-sulfidation deposits in this area are characterized for being base-metals poor systems.; Regional gravity and magnetic data indicate that these major systems were emplaced in zones with specific geophysical characteristics, such as a transition from a large negative gravity anomaly to a high gravity zone, and a region with different magnetic characteristics.