Journal article
Post-collisional alkaline magmatism as gateway for metal and sulfur enrichment of the continental lower crust
ML Fiorentini, C LaFlamme, S Denyszyn, D Mole, R Maas, M Locmelis, S Caruso, TH Bui
Geochimica Et Cosmochimica Acta | PERGAMON-ELSEVIER SCIENCE LTD | Published : 2018
Abstract
Mafic and ultramafic magmas that intrude into the lower crust can preserve evidence for metal and sulfur transfer from the lithospheric mantle into the lower continental crust. Here we focus on a series of ultramafic, alkaline pipes in the Ivrea Zone (NW Italy), which exposes deeply buried (6–11 kbar), migmatitic metasedimentary rocks intruded by voluminous basaltic magmas of the Mafic Complex, a major crustal underplating event precisely dated via U/Pb CA-IDTIMS on zircon at 286.8 ± 0.4 Ma. The ultramafic pipes postdate the Mafic Complex and from 100 to 300 m wide cumulate-rich conduits. They are hydrated and carbonated, have unusually high incompatible element concentrations and contain bl..
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Awarded by Centre of Excellence for Core to Crust Fluid Systems, Australian Research Council
Funding Acknowledgements
The authors acknowledge the financial support of the ARC Centre of Excellence for Core to Crust Fluid Systems (CE110001017). ML Fiorentini also acknowledges support from the Australian Research Council through Linkage Project LP120100668 and the Future Fellowship Scheme (FT110100241). Staff at the Centre for Microscopy and Microanalysis at the University of Western Australia is kindly thanked for support in the use of the analytical infrastructure. We also acknowledge Boswell Wing for supporting access to the analytical facility at McGill University as well as Peter Koelleger for initial involvement in the project. Dennis Sugiono is thanked for graphic support whereas Marilena Moroni and Gianluca Sessa are thanked for discussion and support with field logistics. Most importantly, Giorgio Garuti and Federica Zaccarini are thanked for providing key samples for U/Pb geochronology and multiple sulfur isotope analysis as well as for sharing their invaluable expertise on the Ivrea Zone. The authors acknowledge the facilities and technical assistance of the Australian Microscopy and Microanalysis Research Facility at the CMCA, UWA. This is contribution 1028 from the ARC Centre of Excellence for Core to Crust Fluid Systems (http://www.ccfs.mq.edu.au). We also would like to thank the editorial handling of GCA Executive Editor Marc Norman, GCA Associate Editor Weidong Sun, as well as the constructive and insightful reviews of Chusi Li and an anonymous reviewer.