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The Hadamengou gold deposit in Baotou City, Inner Mongolia is an important large gold deposit in the Wulashan - Daqingshan metallogenic belt, with great prospecting potential. To give full play to remote sensing technology in geological prospecting, this study extracted the mineralization alteration information of the Hadamengou gold deposit from remote sensing data of different satellites. Based on the spectral characteristics of alteration minerals in the mining area, this study proposed a comprehensive processing method that extracted iron staining information from the Landsat8 OLI and WorldView - 3 data, hydroxyl information from the ASTER and WorldView -3 data, and carbonation information from the ASTER data through principal component analysis. As a result, two alteration zones were delineated based on the distribution patterns of alteration anomalies and the geological map analysis of the mining area. By combining the study results of the ore - controlling structures, it is believed that the metallogenic hydrothermal proceeses of the Hadamengou gold deposit were closely related to structures. This study can provide a reference for the prospecting for the same type of gold deposits in the Wulashan - Daqingshan metaHogenic belt and can guide the peripheral prospecting of the Hadamengou gold deposit. [ABSTRACT FROM AUTHOR]

[Display omitted] • SEDE genesis is most plausible for the first episode of mineralization in the Zhaxikang and Keyue deposits. • A genetic relationship must exist between the Zhaxikang and Keyue deposits. • The Zhaxikang and Keyue deposits have the same metal origins and experience similar ore formation and ore-forming fluid evolution. • Zn–Cd isotopes have the potential to apply in ore deposit research and mineral exploration. The Keyue Sb–Pb–Zn–Ag deposit is a medium-sized deposit near the super-large Zhaxikang Sb–Pb–Zn–Ag deposit within the North Himalayan Metallogenic Belt (NHMB). These two deposits, separated only by a regional NS-trending normal fault with strike-slip properties, have similar ore-forming elements and mineral associations, ore characteristics, ore paragenetic sequence, wall rocks, and H–O–S–Pb isotopic and fluid inclusion characteristics. Herein, we establish Zn–Cd isotopic connections between these two proximal ore deposits. As a means to draw comparisons, we conducted Zn–Cd isotopic research of the Keyue deposit to compare it with that of the Zhaxikang deposit. Both the δ66Zn and δ 114/110Cd values of sphalerite from the Keyue deposit display a temporally decreasing trend from stage 2 (δ66Zn: 0.15‰–0.58‰, average value = 0.29‰; δ 114/110Cd: –0.23‰ to 0.38‰, average value = 0.05‰) to stage 3 (δ66Zn: –0.28‰ to 0.12‰, average value = –0.06‰; δ 114/110Cd: –0.38‰ to –0.32‰, average value = –0.35‰), which was also found in the Zhaxikang deposit. A simple three-phase separation distillation models this temporally decreasing trend, which resulted from the Zn–Cd isotopic fractionation that is most likely related to vapor–liquid-solid dynamics of ore-forming fluid. This distillation model was further augmented by the general geochemical characteristics and fluid inclusion data. A congruence among several geological and geochemical evidence points to the genetic relationships between these two ore deposits that have the same metal origins and experience similar ore formation processes. A three-phase separation model has been established to imitate this evolution, which reveals substantial exploration potential for Zn–Cd at depths below 4100 m within the Zhaxikang orefield. In summary, Zn–Cd isotopes have the potential to trace metal sources, monitor fluid evolution, constrain ore formation, and provide insights into mineral exploration. [ABSTRACT FROM AUTHOR]

The study presents copper (Cu) isotope data of mineral separates of chalcopyrite from four drill core samples in the Miocene Dabu porphyry Cu-Mo deposit formed in a post-collisional setting in the Gangdese porphyry copper belt, southern Tibet. Copper isotope values in hypogene chalcopyrite range from –1.48‰ to +1.12‰, displaying a large variation of up to 2.60‰, which demonstrates Cu isotope fractionation at high-temperature during hydrothermal evolution. The majority of measured chalcopyrite isotopic compositions show a gradual increasing trend from –1.48‰ to +1.12‰ with the increase of drilling depth from 130m to 483m, as the alteration assemblages change from potassic to phyllic. Similarly, the other δ 65 Cu values (δ 65 Cu = (( 65 Cu/ 63 Cu) sample /( 65 Cu/ 63 Cu) standard − 1) × 1000) of the chalcopyrite show a gradual increasing trend from −1.48‰ to +0.59‰ with the decrease of drilling depth from 130 m to 57 m, as the alteration assemblages change from potassic, phyllic, through argillic to relatively fresh. These observations suggest a genetic link between Cu isotope variation and silicate alteration assemblages formed at different temperatures, indicative of a Rayleigh precipitation process resulting in the large variation of δ 65 Cu values at Dabu. In general, samples closest to the center of hydrothermal system dominated by high-temperature potassic alteration are isotopically lighter, whereas samples dominated by low-temperature phyllic alteration peripheral to the center are isotopically heavier. The predicted flow pathways of hydrothermal fluids are from No. 0 to No. 3 exploration line, and the lightest δ 65 Cu values are the most proximal to the hydrothermal source. Finally, we propose that the northwest side of the No. 0 exploration line has high potential for hosting undiscovered orebodies. The pattern of Cu isotope variation in conjunction with the features of silicate alteration in porphyry system can be used to trace the hydrothermal flow direction and to guide mineral exploration. [ABSTRACT FROM AUTHOR]

[Display omitted] • The alteration zone patterns have been identified based on the SWIR data at Demingding. • The relationship between Pos2200 and compositions of white mica has been demonstrated by EPMA and determined the subspecies in the ore and barren zone. • We predicted the center of hydrothermal/mineralization based on the spatial variations of the white mica SWIR scalars. The Demingding Cu–Mo deposit, found in the eastern Gangdese metallogenic belt in China, has a significant exploration potential. Detailed field studies coupled with short-wavelength infrared (SWIR) spectroscopy and electron probe micro analyses (EPMA) identified a total of 15 alteration minerals such as white mica group minerals, chlorite, kandite, and smectite groups. The study also discovered the spatial distribution of alteration zone patterns, including phyllic, propylitic, and intermediate argillic alterations. Furthermore, variations were observed in the Al-OH absorption position (Pos2200) of the white mica group with variable Al-Si-Fe-Mg content. Most of the white micas in the ore zone were muscovitic series, whereas the barren zone contained phengitic series micas. Some micas have undergone a transition to illite due to low-temperature alteration overprinting. The western part of the deposit exhibited lower Pos2200, higher SWIR-IC, and higher Dep2200 values, implying an intense phyllic alteration and higher paleotemperatures. These characteristics suggest that the area is in close proximity to the hydrothermal center and fluid channel. Therefore, it was identified as an exploratory target for buried copper ore bodies. The SWIR spectra of the white mica group can be used for exploration in other similar porphyry deposits. Under acidic conditions, shorter Pos2200 and higher SWIR-IC can be used as indicators for hydrothermal or mineralization centers. [ABSTRACT FROM AUTHOR]