Peru Geology
GEOLOGY AND METALLOGENY OF THE PERUVIAN ANDES

Active and paleo-convergent margins host a diverse array of some of the world's richest gold, copper, zinc, lead and silver deposits. Within the Peruvian segment of the Andean Cordillera, world-class deposit styles that are currently being exploited include:

- porphyry copper - (gold, molybdenum)
- high sulphidation epithermal gold - (silver)
- low sulphidation gold - silver.
- iron oxide copper - gold.
- zinc - copper - lead - silver skarn.
- zinc - lead - silver manto and chimney.

Although much of this mineral wealth can be attributed to magmatic pulses at key ages within the last 70 million years, the geological setting of major deposits is related to structures that have been active since the early Paleozoic.

The modern day Andean Cordillera is principally the result of a 240 million year history of subduction-related tectonism along the western margin of the Brazilian Shield, which began in the Early Triassic and continues today. This long-lived cycle of east directed subduction beneath the South American Plate (termed the Andean Cycle) formed a linear volcano-plutonic arc with a landward back arc basin, along what was the coast of Peru. Magmatism along the arc was episodic, being regularly disrupted by shortening events that caused inversion of the back arc volcano-sedimentary sequences, and migration of the center of volcanism and intrusion.

With few exceptions, the major ore systems known from Peru are associated with arc-related igneous and volcanic rocks. Metallogenic zoning is characteristic of continental margin activity where early episodes are dominated by copper-gold mineralisation close to the subduction trench, progressing to zinc-lead then tin-tungsten systems further inside the continental margin.

Major Metallogenic Belts and Deposits of Peru