Petrogenesis of Transitional Large Igneous Province: Insights From Bimodal Volcanic Suite in the Tarim Large Igneous Province. Issue 5 (6th May 2020)

• Record Type: Journal Article
• Authors: Cheng, Zhiguo; Zhang, Zhaochong; Wang, Zhenchao; Wang, Fangyue; Mao, Qian; Xu, Lijuan; Ke, Shan; Yu, Huimin; Santosh, M.
• Is Part Of: Journal of geophysical research. Volume 125:Issue 5(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-05-06
• Subjects: transitional LIP -- MASH -- AFC -- hydrous crust -- plume‐orogenic interaction; Geomagnetism -- Periodicals; Geochemistry -- Periodicals; Geophysics -- Periodicals; Earth sciences -- Periodicals; 551.1
• DOI: 10.1029/2019JB018382
• Languages: English
• ISSNs: 2169-9313

Abstract

Abstract: The Tarim large igneous province (TLIP) corresponds to a transitional large igneous province based on the high proportion of felsic rocks, classifying between mafic and silicic large igneous provinces. Here we investigate a bimodal suite including trachydacite, rhyolite, and basanite from the Northern Tarim Uplift using petrological, geochemical, stable, and radiogenic isotopic techniques with a view to understand the formation of the TLIP. Our study reveals a multistage origin involving multiple components, although the various rock suites are genetically linked and formed under a rift incubation setting related to mantle plume. The low δ 26 Mg values (−0.48‰ to −0.71‰), Fe/Mn > 60, FC3MS (FeO T /CaO‐3*MgO/SiO2 ) > 0.65, and high TiO2 contents (4.45–4.93 wt.%) of basanite from this suite suggest formation through partial melting of carbonated eclogite formed by recycled oceanic crust. The thick lithosphere beneath the Tarim Craton promoted extensive interaction between the underplated basaltic magmas and crust‐derived magmas leading to the formation of multistage magma chambers. Geochemical and mineralogical studies suggest that the trachydacite experienced a mixing, assimilation, storage, and hybridization process, whereas the rhyolite was produced by fractional crystallization from the associated mantle‐derived magma with significant crustal contamination. The abundance of amphibole in the trachydacite suggests a hydrous parental magma with H2 O content in the range of 2.75 to 4.05 wt.%. Our results suggest that hydrous crustal components contributed significantly in the formation of voluminous felsic rocks of the TLIP. Key Points: Tarim large igneous province (TLIP) is suggested to be a transitional LIP MASH and AFC processes account for the generation of the voluminous felsic rocks A plume‐orogenic interaction model is proposed for TLIP and CAOB