Journal
MINERALIUM DEPOSITA
Volume 40, Issue 2, Pages 175-191Publisher
SPRINGER
DOI: 10.1007/s00126-005-0480-1
Keywords
La Caridad; porphyry Cu; U-Pb; Re-Os; Sonora; Mexico
Categories
Ask authors/readers for more resources
Uranium-lead zircon (laser ablation multicollector ICP-MS spot analysis) ages from La Caridad porphyry copper deposit in the Nacozari District, Northeastern Sonora, Mexico, suggest a short period of magmatism, between 55.5 and 52.6 Ma. Two U-Pb ages from the mineralized quartz monzonite unit, showing different textural characteristics, yielded indistinguishable crystallization ages (similar to 54 Ma), and indicate that the intrusion responsible for the mineralization occurred as a single large complex unit, instead of multiple pulses of magmatism. Some zircons analyzed also show inherited ages in cores recording dates of 112-124 Ma, 141-166 Ma and 1.4 Ga. The Re-Os molybdenite ages from the potassic and phyllic hydrothermal alteration veins yielded identical ages within error, 53.6 +/- 0.3 Ma and 53.8 +/- 0.3 Ma, respectively (weighted average of 53.7 +/- 0.21 Ma), supporting a restricted period for the mineralization. The geochronological data thus indicate a short-lived magmatic and hydrothermal system. The inherited zircons of Precambrian and Late Jurassic-Mid Cretaceous age found in the intrusive rocks of La Caridad deposit, can be explained considering two possible scenarios within the tectonic/magmatic evolution of the area. The first scenario considers the presence of a Precambrian anorogenic granitic basement that is intruded by Mesozoic (Jurassic-Cretaceous) units present beneath the La Caridad deposit. The second scenario suggests that the Mesozoic Glance Conglomerate Formation of Arizona underlies the Palcocene volcanic-igneous pile in the La Caridad area.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available