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The Tianshan Carboniferous post-collisional rift volcanic rocks occur in northwestern China as a large igneous province. Based on petrogeochemical data, the Tianshan Carboniferous post-collisional rift basic lavas can be classified into two major magma types: (1) the low-Ti/Y type situated in the eastern-central Tianshan area, which exhibits low Ti/Y (<500), Ce/Yb (<15) and SiO2 (43-55%), and relatively high Fe2O3T (6.4-11.5%); (2) the high-Ti/Y type situated in the western Tianshan area, which has high Ti/Y (>500), Ce/Yb (>11) and SiO2 (49-55%), and relatively low Fe2O3T (5.8-7.8%). Elemental data suggest that chemical variations of the low-Ti/Y and high-Ti/Y lavas cannot be explained by fractional crystallization from a common parental magma. The Tianshan Carboniferous basic lavas originated most likely from an OIB-like asthenospheric mantle source (87Sr/86Sr(t) ≈ 0.703-0.705, eNd(0 = +4 to +7). The crustal contamination and continental lithospheric mantle have also contributed significantly to the f
The Tianshan Carboniferous post-collisional rift volcanic rocks occur in northwestern China as a large igneous province. Based on petrogeochemical data, the Tianshan Carboniferous post-collisional rift basic lavas can be classified into two major magma types: (1) the low-Ti / Y type situated in the eastern-central Tianshan area, which exhibits low Ti / Y (<500), Ce / Yb (<15) and SiO 2 (43-55%), and relatively high Fe 2 O 3 T 2) the high-Ti / Y type situated in the western Tianshan area, which has a high Ti / Y (> 500), Ce / Yb 7.8%). Elemental data suggest that chemical variations of the low-Ti / Y and high-Ti / Y lavas can not be explained by fractional crystallization from a common parental magma. The Tianshan Carboniferous basic lavas originated most likely from an OIB-like asthenospheric mantle source (87Sr / 86Sr (t) ≈ 0.703-0.705, eNd (0 = +4 to +7). The crustal contamination and continental lithospheric mantle have also contributed sig nificantly to the f