The Consummate Geoscientist: A Celebration of the Career of Maarten de Wit
CONTAINS OPEN ACCESS
Papers in this special publication mirror Maarten's career as a leading expert on Gondwana evolution and Archean tectonics. Maarten also contributed to our understanding of Archean life, African erosional history and South African shale-gas development, and was a vigorous supporter of the advancement of South African students from varied backgrounds.
Zircon U–Pb, oxygen and hafnium isotopic characteristics of the Neoarchean–Paleoproterozoic Betsiboka Suite, Madagascar: tracing source to sink pathways in Proterozoic and Phanerozoic provenance studies
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Published:October 04, 2023
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CiteCitation
Donnelly Brian Archibald, Alan S. Collins, Sheree E. Armistead, John D. Foden, Justin L. Payne, Théodore Razakamanana, 2023. "Zircon U–Pb, oxygen and hafnium isotopic characteristics of the Neoarchean–Paleoproterozoic Betsiboka Suite, Madagascar: tracing source to sink pathways in Proterozoic and Phanerozoic provenance studies", The Consummate Geoscientist: A Celebration of the Career of Maarten de Wit, A. J. Hynes, J. B. Murphy
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Abstract
The Neoarchean to Paleoproterozoic Betsiboka Suite of Madagascar mainly consists of granitoid orthogneiss and migmatite variably metamorphosed to amphibolite and granulite facies during the late Neoproterozoic. New U–Pb zircon data yield emplacement ages of 2512 ± 17, 2507 ± 17, 2493 ± 14 and 2485 ± 16 Ma. Zircon δ18O data indicate involvement of the continental crust during magma genesis. Mostly positive εHf(t) values plot slightly below the depleted-mantle curve. The isotopic data favour mixing between an older Archean crustal source and a juvenile depleted-mantle source. Possible local crustal candidates for the older component in the exposed Malagasy basement are Neoarchean mafic gneisses in the Tsaratanana Complex and the c. 3200 Ma Nosy Boraha orthogneiss in the Antongil Domain. The new isotopic data support interpretations from previous studies investigating the genesis of Tonian plutonic rocks advocating crustal melting of a Mesoarchean crustal source in the Antananarivo Domain. In addition, detrital zircon in the Proterozoic Ambatolampy Group and Itremo Group probably had a local source with the same isotopic composition as the Betsiboka Suite. Our study demonstrates the significance of multi-isotopic data from zircon for constraining the sources of detrital zircon grains in sedimentary provenance studies.
- absolute age
- Africa
- amphibolites
- Archean
- crust
- gneisses
- granites
- hafnium
- Hf-177/Hf-176
- igneous rocks
- Indian Ocean Islands
- isotope ratios
- isotopes
- Madagascar
- magmatism
- metals
- metamorphic rocks
- migmatites
- Neoarchean
- nesosilicates
- O-18/O-16
- orthogneiss
- orthosilicates
- oxygen
- Paleoproterozoic
- plutonic rocks
- Precambrian
- Proterozoic
- provenance
- silicates
- stable isotopes
- U/Pb
- upper Precambrian
- zircon
- zircon group
- Betsiboka Suite