Ministro Hales is a mega porphyry Cu-(Mo) deposit with the superposition of hydrothermal breccias/stockwork bodies containing Cu-(Ag-As) in its upper part. The porphyry and mineralization make up an elongated body resembling a large dike. It is situated west of a major strand of the West Fault system, an arc parallel set of (early dextral, later sinistral) transcurrent fault active in Cenozoic times. East of the fault, Paleozoic metamorphic, intrusive and volcanic basement rocks dominate, covered by ca. 1000 m of Cenozoic gravels. West of the fault volcanic rocks are intruded by Eocene intrusive bodies. Hypogene mineralization is distributed within a fanning, subparallel array of subvertical hydrothermal breccia bodies with a NS to N15o W elongation, parallel to the West Fault.

Supergene enrichment and oxidation are minor west of the fault, and an exotic oxide blanket occurs in the gravels to the east. Within the deposit, the older rocks are undifferentiated green andesitic flows and breccias with chlorite, epidote and pyrite, assigned to the Triassic Collahuasi Fm., although zircon dates indicate some rocks may be Paleozoic in age. The bulk of the hypogene ore is hosted by the pervasively altered, equigranular MM Granodiorite. It has a Triassic zircon U/Pb LAM-ICPMS age, and is presently considered to be the equivalent to the Este Granodiorite of Chuquicamata.

The dike like MM Porphyry appears deep in the deposit and adjacent to the West Fault; its U ........

Ministro Hales is mined by open pit extraction method.

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