The Maduo-Zaduo continental flood basalts in north-central Tibet: Implications for a large igneous province within the Paleo-Tethyan Ocean

Large igneous provinces (LIPs) are predominantly mafic volcanic provinces emplaced over a short time-period covering vast areas. They provide a direct link between the deep Earth and the atmosphere. Remnants of Early Permian LIP activity have been identified in Central Europe (Skagerrak in the North Sea) and many East Asian blocks (Tarim, Tethyan, and Zaduo). Here we demonstrate that ca. 280 Ma lavas from the Songpan-Ganzi Terrane (Maduo, north-central Tibet) have geochemical signatures of continental flood basalts resembling the similar-aged Zaduo LIP in North Qiangtang. These Tibetan blocks were geographically separated in the Early Permian, but the Maduo and Zaduo lavas together with ocean island basalt-type rocks preserved within the suture zone between the two blocks may have formed part of a single Early Permian LIP that we name the Maduo-Zaduo LIP. LIPs are episodically sourced by plumes from the lowermost mantle. Our plate reconstructions indicate that three Early Permian LIPs (Skagerrak, Tarim, and Tethyan) can be genetically linked to the African large low shear-wave velocity province (LLSVP) near the core-mantle boundary while the Maduo-Zaduo LIP was sourced from the Pacific LLSVP.