The source characteristics and origin of high-Ti (HT) and low-Ti (LT) magma types are the first-order geodynamic question for the Large Igneous Provinces (LIPs) and mantle plume, especially the Emeishan LIP (ELIP). In this study, we report LA-ICP-MS zircon U-Pb ages, as well as mineralogical, geochemical, and Sr-Nd isotopic data on the Late Permian basalts in the Xiaogaoshan, Yanyuan, Sichuan. The Xiaogaoshan basalts can be classified as LT/HT transitional type and sodic tholeiitic rock series. Clinopyroxene crystallization temperature and pressure are 1 061 to 1 180℃ and 190 to 352 MPa. The X_Mt of Fe-Ti oxides (0.24 to 0.38) indicates a relatively low oxygen fugacity environment and the Fenner trend of fractional crystallization (evolving to iron-enriched). The zircon U-Pb data yield age is 260.2±5.0 Ma, i.e., the peak magmatism of the ELIP. The chondrite-normal- ized rare earth elements (REE) patterns and the primitive mantle-normalized spidergrams show oceanic island basalt (OIB) affinity, with a trend to E-MORB (enriched Mid-Ocean Ridge Basalts). The rocks have low age-corrected (⁸⁷Sr/⁸⁶Sr)_i ratios (0.704 650 to 0.705 035) and positive εNd(t) values (+2.91 to +3.02). The geochemical and isotopic features suggest that the lavas have not undergone any significant crustal contamination, and the source is dominated by "plume" components. The Late Permian Xiaogaoshan basalts have a co-genetic relationship with the picritic porphyries in the Pingchuan iron oxide deposit via fractional crystallization. REEBOX PRO modeling of the adiabatic decompression melting for the Emeishan basalts indicate that the mantle sources of the Emeishan basalts are characterized by the primitive mantle (PM). Only HT basalts can be generated at elevated mantle potential temperatures (t_p=1 550℃ to 1 690℃) beneath a lithosphere that is 140 km thick. In contrast, expanded melting temperatures (t_p=1 400℃ to 1 690℃) and regime spread over LT and HT basalts beneath a considerably thinned lithosphere (50 km). Therefore, the origin of the Emeishan basalts, both LT and HT, is through a continuous melting process of the same source. The modelling suggests that the Xiaogaoshan basalts most likely formed under a thinner lithosphere (50 km), with melting temperature and pressure conditions of 1 403℃/2.38×10³ MPa to 1 557℃/3.55×10³ MPa.