Precise ID-TIMS U–Pb baddeleyite ages (1110–1112 Ma) for the Rincón del Tigre–Huanchaca large igneous province (LIP) of the Amazonian Craton: Implications for the Rodinia supercontinent

• We obtained precise U–Pb baddeleyite ages for the Rincón del Tigre and the Huanchaca intrusions.
• The 1110–1112 Ma age for both defines a LIP-mantle plume event in SW Amazonia.
• The LIP-mantle plume event is potentially linked with an evolving Grenville margin.
• There is a tight age match with intraplate magmatism in other crustal blocks.

High quality U–Pb (ID-TIMS) baddeleyite ages define the timing of crystallization of the Rincón del Tigre layered intrusion (1110 ± 2 Ma) and the Huanchaca mafic suite (1112 ± 2 Ma) in the Bolivian Precambrian shield – SW portion of the Amazonian Craton. The identical ca. 1110–1112 Ma ages obtained for each (about 500 km apart) suggest these belong to a previously unrecognized LIP. The large area of distribution and the intraplate geochemistry for the 1110 Ma Huanchaca–Rincón del Tigre rocks support a relationship with mantle plume activity pre-dating Rodinia breakup. Contemporary anorogenic magmatism in Amazonia is probably linked to crustal melting caused by the LIP. The newly identified 1110 Ma LIP has a tight age match with intraplate magmatism in the Congo, Kalahari and Indian cratons, and the Keweenawan event of central Laurentia among others. While a reconstruction history of Amazonia and Laurentia is still a matter of debate on paleomagnetic grounds, a reconstruction link with other crustal blocks remains possible.

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