Journal article

The tectonic domains of southern and western Madagascar

SD Boger, R Maas, M Pastuhov, PH Macey, W Hirdes, B Schulte, CM Fanning, CAM Ferreira, T Jenett, R Dallwig

PRECAMBRIAN RESEARCH | ELSEVIER SCIENCE BV | Published : 2019

Abstract

Southern and western Madagascar is comprised of five tectonic provinces that, from northeast to southwest, are defined by the: (i) Ikalamavony, (ii) Anosyen, (iii) Androyen, (iv) Graphite and (v) Vohibory Domains. The Ikalamavony, Graphite and Vohibory Domains all have intermediate and felsic igneous protoliths of tonalite-trondhjemite-granodiorite-granite composition, with positive εNd, and low Sr and Pb isotopic ratios. All three domains are interpreted to be the products of intra-oceanic island arc magmatism. The protoliths of the Ikalamavony and Graphite Domains formed repectively between c. 1080–980 Ma and 1000–920 Ma, whereas those of the Vohibory Domain are younger and date to between..

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Grants

Awarded by International Development Agency


Awarded by internal University of Melbourne Grant


Funding Acknowledgements

SDB gratefully acknowledges hard work, local knowledge and logistical support of Auguste Razafinjoelina and Theodore Razakamanana, without whose assistance SDB and MP would not have successful completed their 2013 field season. Similar credit also needs to be given to the entire 2005-2007 GAF-BGR support staff and field team, whose efforts made it possible for the authors (SDB, WH, BS, CAMF, TJ and RD) to visit and sample most corners of southern Madagascar. The majority of the research was funded by the International Development Agency (Credit No.: 3754 MAG) and undertaken under the auspices of the Projet de Gouvernance des Ressources Minerales (PRGM - Madagascar). Sr-Nd-Pb isotopic analysis was undertaken with support of an internal University of Melbourne Grant (ECR602698) awarded to SDB. Mr Warrick Joe and Dr. Alan Greig are thanked for assistance with the isotopic and chemical analytical work. Drs. Jorg Giese and Donelly Archibald, together with an anonymous reviewer are thanked for what were extremely thorough, thoughtful, and constructive reviews.