To assess the effects of sediment addition on the partial melting of subducted oceanic crust and generation of arc silicic magma, a series of comparative partial melting experiments on a garnet plagioamphibolite and a 90 wt% garnet plagioamphibolite + 10 wt% plagioclase slate mixture at 850–1,000°C/1.5 GPa were conducted on a Piston-cylinder apparatus. In the experimental products, partial melt coexists with amphibole + plagioclase + garnet + clinopyroxene at 850–950°C and plagioclase + garnet + clinopyroxene at 1000°C. Compared with pure garnet plagioamphibolite, partial melting of mixture get a higher melting percentage and generates the silicic melt with geochemical characteristics of higher Na₂O/K₂O and lower Al₂O₃ in major element and high Rb content in trace element at over 950°C. This result indicates that silicic arc magma may generate from partial melting of metamorphic subducted oceanic crust with sediments thereon, sediment addition contributes to their chemical component and generation dynamic process.

The Great Xing’an Range (GXR) is a significant belt of polymetallic deposits located in the eastern segment of the Central Asian Orogenic Belt. The recently found Huoluotai porphyry Cu (Mo) deposit is situated in the northern GXR region in northeastern (NE) China. The deposit has been studied extensively using field geology and geochronological methods, which have identified two distinct mineralization events. These events include an early occurrence of porphyry-type Cu (Mo) mineralization and a later occurrence of vein-type Cu mineralization. Prior geochronology investigations have determined an approximate age of 147 Ma for the early porphyry-type Cu (Mo) mineralization. ⁴⁰Ar/³⁹Ar dating of K-feldspar of the altered Cu-mineralized quartz diorite porphyry veins for the overprinting vein-type Cu mineralization provides plateau ages of 123.1 ± 1.5 Ma, 122.3 ± 2.8 Ma, and 122.2 ± 0.4 Ma. Sulfide S-Pb isotope compositions of the two mineralization events suggest that both have a magmatic source. The origin of ore-forming metals displays the features of a crust–mantle mixing origin. The regional extensional tectonic setting in NE China during the Early Cretaceous was caused by large-scale lithosphere delamination and upwelling of the asthenospheric mantle. These processes were triggered by the rollback of the Paleo-Pacific Plate. The tectonic event in question resulted in the lithospheric thinning, significant magmatic activity, and mineralization in NE China.