Application of geological and short wavelength infrared (SWIR) spectroscopy mapping in the Mailong gold deposit, East Kunlun: Implications for exploration targeting

• DOI: 10.1016/j.oregeorev.2024.106080
• Publication Date: 2024-05-15T15:29:11Z
• Authors: Hao Wang; Weipin Sun; Hua Li; Xiaoliang Yu; Chao Gu; Cai Ma; Yuzhou Feng; Genshen Cao; Junfeng Zhao; Yabo Zhu; Bing Xiao

Widespread regolith cover makes it difficult to identify the anomalous size of their mineralogical or geochemical footprint at surface in gold exploration. Short wavelength infrared (SWIR) spectroscopy with effective identification clays and other hydrous minerals shows potential application The detailed geological short mapping was conducted newly-discovered orogenic-type Mailong deposit (13.06 t @ 6.29 g/t Au), East Kunlun, determine alteration stage mineral assemblages discuss values SWIR spectral In area, magmatic rocks consist granodiorite, biotite plagiogranite mafic dikes, mineralization a close spatial temporal relationship dikes. earliest chloritization (chlorite-quartz) is widely distributed granodiorite plagiogranite. following potassic (hydrothermal K-feldspar quartz) developed along high-angle fault/fracture, which cut through subsequent sulfide (chlorite-muscovite-sulfide-carbonate) overprints former alteration, association Native occurs fracture arsenopyrite associated such as pyrite, chalcopyrite during early stage. Supergene characterized by limonite malachite. At Mailong, data indicate that most abundant (chlorite, white micas ankerite) mainly occurred northern area. White mica Al-OH absorption longer wavelengths (Pos2200 = 2202.5 ∼ 2203 nm) higher Illite crystallinity (IC 1.2 3.1) probably reflecting temperature pH conduit bottom ZK0001 ZK0801. sharp shift IC near reflects control fault. This area also situated V-shaped intersections three granitic intrusions structural transection, indicating more possible hydrothermal fluid channel than center. Low-grade Au (Au 0.1 0.5 g/t) within channels Pos2200 (mainly 2022.5 3.1), while high-grade endowment dikes has low 2201 0.43 1.2). Meanwhile, an equation distance -15*IC + 31 (R2 0.47) can be summarized for low-grade orebodies vectoring. Integrating data, target areas ore bodies outlined using criteria mica, shorter position nm), lower 1.2), chlorite Fe-OH Pos2250 (>2247 occurrences study demonstrates utilizing conjunction accurate great greenfield exploration orogenic deposits.