Geochemical Constraints of Porphyry Cu Deposits-Forming Magmas in Sonora, Mexico

Porphyry Cu deposits (PCDs) represent the most significant source of economic-grade copper (Cu) on Earth (Sillitoe, 2010). PCD formation is intimately linked to the magmatic and tectonic evolution of convergent margins (Sillitoe, 2010). While the metallogenic characteristics of PCDs have been well-studied, the petrological and geochemical processes that govern magma fertility, essential prerequisites for PCD formation, remain less well constrained. Magma fertility is primarily controlled by variations in pressure-temperature (P–T) conditions, redox state, and volatile content during magmatic evolution (Richards, 2003; Audétat et al., 2008). These factors influence the capacity of magmas to concentrate and transport metals such as Cu. This thesis investigates the geochemical signatures associated with fertile and barren magmatic systems in Sonora, Mexico. Using zircon trace-element geochemistry, U–Pb geochronology, and thermobarometry, I assess the magmatic conditions under which PCDs and barren rocks formed, and identify key proxies, such as REE anomalies, H₂O content, and oxidation state, that distinguish fertile magmas from barren magmatic systems. These findings provide new constraints on the petrogenetic evolution of magmas within the CEMMA and offer insights into the broader geodynamic and metallogenic processes that control porphyry Cu mineralization.

Author dc:creator

• Oscar Daniel Torres Alarcon (23292127)

• Economic geology

Statement dc:rights

• In Copyright
• Open Access after 2028-01-01

DOI dc:identifier

https://doi.org/10.25417/uic.31451866.v1

OAI identifier oai:identifier

oai:figshare.com:article/31451866