Abstract
This issue (APE 134:1), containing four articles, concludes the first issue of volume 134 of the Applied Earth Science journal, and it is the first issue for the year 2024. The papers present case studies of mineral deposits’ geology and exploration models encompassing different commodities and mineralisation types. The submissions were obtained from academic and research centres located in four countries, Canada, China, Brazil and Uzbekistan.
Together, the four studies demonstrate developments in resource discovery, geological characterisation and mining and mineral processing technology. In order to improve spatial predictions and estimation accuracy, the first study presents Filtered Kriging with Parametric Error (FKPE), a unique geostatistical technique for managing different sample mistakes in mining. In the second study, mine fire detection is addressed by combining infrared remote sensing with firefly and particle swarm optimisation methods to improve the accuracy (99.48%) and efficiency (51.92%) of identifying hidden fire sources, lowering safety concerns.
Ground-penetrating radar (GPR) is suggested for better fracture analysis in the third study, which focuses on the geological characterisation of Pit 9 quarry in Brazil, finding three marble kinds and highlighting the effects of folding and intrusive dikes on rock integrity. The fourth study explores the mineral resources of the Kuljuktau Mountains, identifying graphite, lithium and high-purity quartz deposits with potential for green energy applications and using U-Pb zircon dating to refine the region's metallogenic chronology. In order to maximise mineral exploration, mining safety and sustainable resource exploitation, these studies collectively highlight the significance of combining geostatistics, remote sensing, geological modelling and resource evaluation.
The first paper by Silva et al. 1 entitled ‘Kriging Data with Measurement Error: A Review and a Generalized Approach’. This research concluded that by addressing the shortcomings of current kriging techniques, the FKPE method offers a thorough framework for integrating various error types into geostatistical predictions. Filtered Kriging with Parametric Error enhances spatial dependence estimates by using error-free covariograms and the error models that go along with them, eliminating the need for independent modelling for each subset and cross-covariance. This approach is a strong tool for mining applications and is especially useful for managing grade-proportional, heteroscedastic and self-correlated mistakes. The study provides an organised approach to implementation by outlining methods for estimating covariograms and error models. To further increase FKPE's usefulness in resource estimate, future studies should investigate its use in situations involving numerous data sources and geostatistical simulations.
The second paper is authored by Feng and Xue 2 entitled ‘Infrared Remote Sensing Inversion Technology for Hidden Fire Sources in Mine Fire Areas - Joint GSO and PSO Algorithms’. The authors concluded that by precisely identifying concealed fire sources, the suggested HFS position IRS inversion model effectively gets beyond the drawbacks of conventional fire detection techniques. In comparison to stand-alone optimisation techniques, the model's integration of GSO and PSO greatly improves detection accuracy, convergence speed and computational economy. With precise temperature and position estimates for a range of fire source settings, the testing findings validate its superiority. The stability of temperature data, however, may be impacted by outside variables like the weather, and scalability issues may surface with greater detection regions because of computational expenses. To increase the model's usability and real-time application, future studies should investigate lightweight models, parallel computing strategies and validation through intricate field tests. In the end, this research contributes to improved safety and risk management in mining operations by offering a very effective and precise framework for mine fire detection.
The third paper, written by Hartwig et al. 3 entitled ‘Geological and Structural Controls on Marble Quarrying and Aesthetic Patterns: Espírito Santo State (Brazil)’. In this study, three types of marble – calcite, dolomite and banded – were found by the geological characterisation of Pit 9 quarry in Itaoca, Espírito Santo, Brazil. These types were differentiated by heterogeneous and discontinuous metamorphic banding made up of carbonates (60%) diopside (25%) and tremolite (15%). Two folding phases were identified by structural research as having an impact on the marble's appearance and extraction capability. The first phase had tight, isoclinal folds, whereas the second phase had open folds. Thick felsic dikes cause fracture, which compromises the integrity of the rock, while intrusive granite and metamafic dikes produce narrow halos of contact metamorphism. The rock mass at the mining level has poor fractures and primarily non-persistent joints in spite of these intrusions. To optimise marble extraction, it is recommended to use GPR to better assess rock fracturing patterns, employ selective extraction techniques to minimise dike-related degradation and conduct further studies on mechanical properties and weathering resistance. These insights support efficient marble resource management while ensuring high-quality material extraction.
The final paper in this issue is written by Mirkamalov et al. 4 entitled ‘Geology of critical mineral deposits of the Kuljuktau Mts., Central Kyzylkum (Uzbekistan)’. The authors discussed that significant key mineral resources, such as Taskazgan graphite, Shaidaraz lithium and Tozbulak high-purity quartz deposits as well as possible rare earth mineralisation, can be found in Uzbekistan's Kuljuktau Mountains. According to geological research, thrust tectonics and magmatism throughout the Ordovician-Silurian and Carboniferous-Permian periods shaped the area along with an active continental border. Oceanic tholeiites and intraplate basalts are associated with andesitic and rhyolitic formations, whereas ensialic island arc settings are associated with andesite–dacite–rhyolite formations. The metallogenic framework of the region is refined by U-Pb zircon dating of the Kuljuktau and West Tozbulak intrusive complexes (353.0 ± 4 Ma and 349.6 ± 6.8 Ma). The Taskazgan graphite deposit is a priority for resource development since it is housed in gabbroids and contains valuable by-products such as Ni, Co and PGEs. Moreover, Lepidolite–spodumene pegmatites are linked to lithium mineralisation, which calls for more research. Uzbekistan's shift to a green economy could be aided by the manufacture of metallic silicon from the Tozbulak high-purity quartz resource, which is housed in leucogranites. Further investigation could greatly increase the region's economic potential, particularly in pegmatites that are rich in lithium.
The issue's editor believes that information presented in these papers will be of great interest and use for research and exploration geologist worldwide, working in geologically similar terrains and hope that this issue will spark an interest in the geology, ore resources and metallogeny of the regions presented in this issue, which are relatively new for readers of the Applied Earth Science journal.