This paper presents systematic petrological, whole-rock geochemical, and Sr-Nd-Pb isotopic studies on the mafic–ultramafic rocks of the Daaobaogou Ni-Cu sulfide deposit in the Dunhuang Block, Gansu Province. This study aims to reveal the nature of its source region, parent magma composition, and magma evolution processes. The results indicate that the parent magma of the ore-bearing intrusion in Daaobaogou originated from an enriched lithospheric mantle metasomatized by Paleozoic subduction processes. It exhibits high-magnesium characteristics and represents the product of a certain degree of evolution from a primitive magma. The magma evolution underwent significant fractional crystallization, with olivine beginning to crystallize at 1328 °C, following the crystallization sequence: olivine, clinopyroxene, plagioclase, and orthopyroxene. Sr-Nd-Pb isotopes and trace elements indicate that the magma experienced intense crustal contamination (approximately 10–20% upper crust) during its ascent.
Wang et al. (Mon,) studied this question.