Project

Back to overview

Magmatic-hydrothermal transition in the world class Sn District of San Rafael, Peru: multi-isotopic characterization

English title Magmatic-hydrothermal transition in the world class Sn District of San Rafael, Peru: multi-isotopic characterization
Applicant Fontboté Lluis
Number 169901
Funding scheme Project funding
Research institution Département des sciences de la Terre Université de Genève
Institution of higher education University of Geneva - GE
Main discipline Geochemistry
Start/End 01.03.2017 - 28.02.2019
Approved amount 237'116.00
Show all

Keywords (4)

Tin deposits; Andean metallogeny; Tourmaline; Boron isotopes

Lay Summary (French)

Lead
L'etain est un élément relativement rare qui a des nombreux usages. Il est à la base de nombreux alliages et est utilisé aussi dans l'industrie chimique et pharmaceutique. Le projet cherche à comprendre mieux l'origine d'un des types principaux de gisements d'étain.
Lay summary

Le projet  prend comme exemple le gisement d'étain le plus riche du monde, San Rafael au Sud de Pérou, où l'etain se presnet sou la forme de cassiterite (SnO2). Il est situé dans la partie septentrionale de la ceinture stannifère des Andes Centrales, caractérisée par des gisements associés a des granites peralumineux typiques d'une formation dans une croûte continentale épaisse.

La caractérisation géochimique et isotopique des échantillons représentatifs des différents stades de la formation du gisement, sélectionnés à des différentes profondeurs et zones dans le district minier  illustrera l'évolution des fluides formateurs du gisement, depuis le stade magmatique aux différentes étapes hydrothermales. Ainsi, dans le cadre du projet, un étude  multi-isotopique de B-O-Sr-Nd-Pb et d'éléments trace sur plusieurs générations de  tourmaline et d'autres minéraux sera réalisé en utilisant des techniques analytiques de pointe y compris le la sonde ionique du SwissSIMS.  La tourmaline été choisie car la composition chimique et isotopique de ce borosilicate, en raison de sa structure et composition complexe, permet de bien tracer les conditions de formation du minerai. Il sera possible d'étudier la transition magmatique-hydrothermale, phase critique de la formation de San Rafael et des nombreux autres gisements.

Direct link to Lay Summary Last update: 08.03.2017

Responsible applicant and co-applicants

Employees

Name Institute

Publications

Publication
Ore Deposits of the Central Andes
Fontboté Lluís (2018), Ore Deposits of the Central Andes, in Elements, 14(4), 257-261.
Sulfide Minerals in Hydrothermal Deposits
Fontboté Lluís, Kouzmanov Kalin, Chiaradia Massimo, Pokrovski Gleb S. (2017), Sulfide Minerals in Hydrothermal Deposits, in Elements, 13(2), 97-103.

Collaboration

Group / person Country
Types of collaboration
Lukas Baumgartner, UNIL Switzerland (Europe)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
- Research Infrastructure
Dr. Andrea Dini, Isti. Geoscienze e Georisorse - CNR, Pisa Italy (Europe)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
- Research Infrastructure
Prf. Alain Chauvet CNRS and UNiv Montpellier France (Europe)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
Prof. Torsten Venemann/UNIL Switzerland (Europe)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
- Research Infrastructure
Dr. Jean Vallance, PUCP, Lima Peru (South America)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
Prof. Urs Schaltegger, Dr. Massimo Chiaradia, UNIGE Switzerland (Europe)
- Publication
- Research Infrastructure

Associated projects

Number Title Start Funding scheme
160071 Fluids and ore forming processes in the continental crust (cont) 01.04.2015 Project funding
177026 Re-equiping the noble gas laboratory to perform state of the art science, University of Geneva 01.03.2018 R'EQUIP

Abstract

The project tackles specific aspects of the magmatic hydrothermal transition at the world class Sn-Cu district of San Rafael, southern Peru, associated with peraluminous granitic magmatism. The post-doc project aims at developing a multi-isotopic B-O-Sr-Nd-Pb and trace element study integrating in situ LA-ICPMS and SIMS and bulk TIMS analyses on tourmaline as a tracer of magmatic-hydrothermal transition processes. Tourmaline tracing will be complemented by analyses of cassiterite and sulfide samples from the Main ore and the post-Main ore stages, along vertical and lateral profiles in the San Rafael system. The geochemically and isotopically characterization of representative samples of the different geochemical stages, selected from different depths and areas in the mining areas will illustrate the mechanisms how hydrothermal fluids that were issued by crystallizing magmas evolve and form different types of ores at different depositional levels. The hypothesis will be tested if, as it seems likely in comparison with mineralizing systems in linked to calcalkaline magmatism, the San Rafael fluid evolution, related to peralkaline magmatism, responds to a single magmatic-hydrothermal path.Analyses will be performed in the in-house facilities and in collaboration with the SwissSIMS facility at the University of Lausanne, ETH Zurich and CNR-Pisa.Most samples are already available but a field season to complement sampling and to get a direct insight on the ore district is foreseen. The project runs in parallel with an already on-going PhD project focused on the relationship of mineralization with the structural and petrological evolution at San Rafael.
-