Geochemistry, U-Pb geochronology and Hf isotope studies of the Daheishan porphyry Mo deposit in Heilongjiang Province, NE China

Abstract

The Daheishan porphyry Mo deposit was recently discovered in the northern segment of the Great Xing'an Range, NE China. Three main types of granitoids are identified in this deposit: granodiorite, fine-grained granite, and porphyritic granite. The orebodies are dominantly hosted within the granodiorite and in the contact zone between the granodiorite and tuff or hornfels, while no mineralization has been found in the fine-grained granite or the porphyritic granite. We present in situLA-ICP-MS zircon U-Pb dates for the granodiorite, fine-grained granite, and porphyritic granite, which yielded 146.9 ± 1.1 Ma (2σ), 146.6 ± 1.7 Ma (2σ), and 149.7 ± 4.2 Ma (2σ), respectively. Their εHf(t) values range from 3.9 to 12.2, associated with young crustal model ages (TDM2) ranging from 524 Ma to 849 Ma, indicating that their parental magmas may have been generated by partial melting of the Neoproterozoic-Cambrian crustal components. The formation of the Daheishan deposit was genetically related to the subduction of the Paleo-Pacific Plate. © 2014 The Society of Resource Geology.