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Recent decades have seen an exponential rise in the application of machine learning in geoscience. Fundamental differences distinguish geoscience data from most other data types. Geoscience datasets are typically multi-dimensional, and contain 1-D (drillholes), 2-D (maps or cross-sections), and 3-D volumetric and point data (models/voxels). Geoscience data quality is a product of its resolution and the precision of the methods used to acquire it. The dimensionality, resolution, and precision of each layer within a geoscience dataset translates to limitations in spatiality, scale and uncertainty of resulting interpretations. Historically, geoscience datasets were overlaid cartographically, to incorporate subjective, experience-driven knowledge, and variances in scale, and resolution. The nuances and limitations that underpin the reliability of automated interpretation are well understood by geoscientists, but are rarely appropriately transferred to data science. However, for true integration of geoscience data, such issues cannot be overlooked without consequence. To apply data analytics to complex geoscience data (e.g., hydrothermal mineral systems) effectively, methodologies must be used that characterise the system quantitatively, using collocated analyses, at a common scale. This paper provides research and exploration insights from an innovative district-wide, scale-integrated, geoscience data project, which analysed 1,590 samples from 23 mineral deposits and prospects across the Cloncurry District, Queensland, Australia. Ten different analytical techniques, including density, magnetic susceptibility, remanent magnetisation, anisotropy of magnetic susceptibility, radiometrics, conductivity, scanning electron microscopy (SEM)-based automated mineralogy, geochemistry, and short-wave infrared (SWIR) hyperspectral data with 561 columns of scale-integrated data (+2151 columns of SWIR). All data were collected on 2 cm x 2.5 cm sample cylinders; a scale at which the confidence in coupling of data from techniques can be high. These data are integrated by design, to eliminate the need to downscale coarser measurements via assumptions, inferences, inversions, and interpolations. This scale-consistent approach is critical to the quantitative characterisation of mineral systems and has numerous applications to mineral exploration, such as linking alteration paragenesis with structural controls and petrophysical zonation. [ABSTRACT FROM AUTHOR]

The Xiong'ershan district in central China hosts broadly coeval porphyry Au (Qiyugou deposit), porphyry Mo (Leimengou deposit), and barren (Huashan pluton) systems. The key controls on the ore potential and different mineralization styles in these systems are not well understood, with first-order differences in fluid chemistry and melt sources being the main alternatives. The fluid inclusion characteristics of all three porphyry systems have been studied using an integrated approach that combines field geology, petrography, microthermometry, and laser ablation-inductively coupled plasma-mass spectrometry analysis of single fluid inclusions. The results permit a reconstruction of the magmatic-hydrothermal evolution of the ore-forming fluids, and to elucidate whether specialized hydrothermal fluids strongly enriched in ore metals (i.e., Mo, Au, Cu) were essential to form the economically significant deposits. The fluid compositions across the three hydrothermal stages from the Qiyugou Au deposit remain approximately the same over time, suggesting that progressive magma fractionation, fluid-rock reaction along fluid path, and mineral precipitation had a limited effect on fluid composition. The syn-ore stage fluids of the Leimengou Mo deposit are characterized by higher Cs/Na, Sr/Na, and B/Na, but lower K/Na and Cl/Na ratios, and also have salinities and homogenization temperatures distinct from the earlier fluids. This demonstrates that Mo mineralization was caused by a second pulse of fluid input from a highly fractionated felsic magma subsequent to the pre-ore stage. At the Huashan barren pluton, fluids from phase II have higher Cs/Na, B/Na, Li/Na, and Rb/Na ratios with lower homogenization temperatures than fluids occurring in porphyritic rocks of phase III, reflecting a higher degree of magma fractionation of this plutonic complex. The Huashan pluton does not host economic mineralization which is likely caused by the low ore metal tenor, inefficient fluid extraction from the melt, or the flat-roof geometry preventing accumulation of a large volume of fluid in the apical part. The Au tenor of the Qiyugou deposit was most likely contributed by mantle-derived material of higher Mg/Na, Fe/Na, Pb/Na, and Zn/Na ratios. Taken together, the metal charged magmatic-hydrothermal fluids, steeply dipping geometry, and small volume of the porphyry stocks all suggest that a much larger magma chamber feeding the porphyry systems should be present at deeper levels with good potential for Mo mineralization below the current level of exposure at Qiyugou deposit. [ABSTRACT FROM AUTHOR]