Abstract:
Nanling scientific deep drilling NLSD-2 is one of the key projects for deep resource exploration in China, which has great significance for understanding the deep geological characteristics and metallogenic regularity of Pangushan tungsten deposit in Nanling. The infrared spectroscopy (400~2 500 nm), XRF elemental scanning and electron microprobe techniques were systematically integrated for the first time in this research to reveal the distribution of deep mineral assemblages, element enrichment characteristics and the evolution of Muscovite metallogenic temperature. The results show that the lithological interfaces can be effectively distinguished by the mineral assemblages such as quartz, muscovite and chlorite identified by infrared spectroscopy. The XRF element analysis shows that W, Pb, Zn and other metallogenic elements are significantly enriched in the metamorphic sandstone layer and the top of the granite, which is consistent with the spatial distribution of the tungsten ore body. The short-wave infrared spectral characteristics of muscovite are affected by chemical composition and metallogenic temperature. The ore-forming related muscovite is characterized by at around Pos2200 near 2 204 nm, relative intermediate ore-forming temperature, rich in Al and poor in Si, Fe, Mg relatively, combined with the electron microprobe temperature. This study has confirmed the high efficiency of infrared spectroscopy and XRF technology in extracting deep mineralization information, but the identification of vein mineralization needs to be combined with imaging spectroscopy. The results could provide a multi-dimensional symbol of mineral-element-temperature for deep tungsten prospecting in Nanling, and promote the innovation of deep resource exploration technology.