Exploration
Mojtaba Bazargani Golshan; Mehran Arian; Peyman Afzal; Lili Daneshvar Saein; Mohsen Aleali
Abstract
The aim is to use the Concentration-Volume (C-V) fractal model to identify high-quality parts of coal seams based on sulfur and ash concentrations. In the K1 and K7 coal seams in the North Kochakali coal deposit, 5 and 6 different populations of ash and sulfur content were obtained based on the results. ...
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The aim is to use the Concentration-Volume (C-V) fractal model to identify high-quality parts of coal seams based on sulfur and ash concentrations. In the K1 and K7 coal seams in the North Kochakali coal deposit, 5 and 6 different populations of ash and sulfur content were obtained based on the results. According to this model, sulfur and ash concentrations below 1.81% and 33.1% for the K7 seam, and below 4.46% and 37.1% for the K1 seam, respective base on Russian standard for ash and high sulfur content of North Kochakali coals were considered as appropriate values. In order to identify the high-quality parts of K1 and K7 coal seams, plans at different depths were used based on the C-V fractal model. Plans at different depths suggests that the southern part of the K1 seam and the northern part of the K7 seam have the highest-quality based on sulfur and ash concentrations, which should be considered in the extraction operation. The logratio matrix was used to compare the results of the C-V fractal model with the geological data of pyrite veins and coal ash. This matrix indicates that sulfur content above 3.8% for the K7 seam and above 4.41% for the K1 seam have good and very good correlation with pyritic veins of geological data, respectively. There are good overall accuracy (OA) values in the correlation between parts of the seam with ash concentration above 37.1% and 45.7% for the K1 and K7 seams, respectively, and the coal ash obtained from the geological data.
Exploitation
F. Soltani; P. Moarefvand; F. Alinia; P. Afzal
Abstract
The traditional approaches of modeling and estimation of highly skewed deposits have led to incorrect evaluations, creating challenges and risks in resource management. The low concentration of the rare earth element (REE) deposits, on one hand, and their strategic importance, on the other, enhances ...
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The traditional approaches of modeling and estimation of highly skewed deposits have led to incorrect evaluations, creating challenges and risks in resource management. The low concentration of the rare earth element (REE) deposits, on one hand, and their strategic importance, on the other, enhances the necessity of multivariate modeling of these deposits. The wide variations of the grades and their relation with different rock units increase the complexities of the modeling of REEs. In this work, the Gazestan Magnetite-Apatite deposit was investigated and modeled using the statistical and geostatistical methods. Light and heavy REEs in apatite minerals are concentrated in the form of fine monazite inclusions. Using 908 assayed samples, 64 elements including light and heavy REEs from drill cores were analyzed. By performing the necessary pre-processing and stepwise factor analysis, and taking into account the threshold of 0.6 in six stages, a mineralization factor including phosphorus with the highest correlation was obtained. Then using a concentration-number fractal analysis on the mineralization factor, REEs were investigated in various rock units such as magnetite-apatite units. Next, using the sequential Gaussian simulation, the distribution of light, heavy, and total REEs and the mineralization factor in various realizations were obtained. Finally, based on the realizations, the analysis of uncertainty in the deposit was performed. All multivariate studies confirm the spatial structure analysis, simulation and analysis of rock units, and relationship of phosphorus with mineralization.
Exploitation
F. Aliyari; P. Afzal; J. Abdollahi Sharif
Abstract
The Zarshuran Carlin-like gold deposit is located at the Takab Metallogenic belt in the northern part of the Sanandaj-Sirjan zone, NW Iran. The high-grade ore bodies are mainly hosted by black shale and cream to gray massive limestone along the NNE-trending extensional fault/fracture zones. The aim of ...
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The Zarshuran Carlin-like gold deposit is located at the Takab Metallogenic belt in the northern part of the Sanandaj-Sirjan zone, NW Iran. The high-grade ore bodies are mainly hosted by black shale and cream to gray massive limestone along the NNE-trending extensional fault/fracture zones. The aim of this investigation was to determine and separate the gold mineralized stages based on the surface litho-geochemical Au, Hg, and As data using the Concentration-Area (C-A) fractal model and stepwise factor analysis in the Zarshuran gold deposit. Three mineralized stages were determined by the C-A fractal modeling and factor analysis, which were correlated with the mineralized stages from geological studies. The main stage of Au mineralization was higher than 1.995 ppm, which was correlated with the main sulfidation stage, whereas the As and Hg highly intense anomalies (higher than 6409 and 19 ppm, respectively) were associated with the quartz-sulfide veins and veinlets. The results obtained by the C-A fractal model and stepwise factor analysis showed that the main gold mineralized stage occurred in the southern part of the Zarshuran deposit, which was correlated with the geological particulars.
