Exploration
mobin saremi; Abbas Maghsoudi; Reza Ghezelbash; mahyar yousefi; Ardeshir Hezarkhani
Abstract
Mineral prospectivity mapping (MPM) is a multi-step and complex process designed to narrow down the target areas for exploratory activities in subsequent stages. To pinpoint promising zones of porphyry copper mineralization in the Varzaghan district, NW Iran, various exploration evidence layers were ...
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Mineral prospectivity mapping (MPM) is a multi-step and complex process designed to narrow down the target areas for exploratory activities in subsequent stages. To pinpoint promising zones of porphyry copper mineralization in the Varzaghan district, NW Iran, various exploration evidence layers were employed in alignment with the conceptual model of these deposits. These layers encompass fault density, proximity to intrusive rocks, multi-element geochemical anomalies, and distances to phyllic and argillic alterations. The geochemical anomaly maps, recognized as the most effective layers, were generated through staged factor analysis (SFA) and the geochemical mineralization probability index (GMPI). Other layers were weighted using a logistic function, and their values were transformed into 0 -1 interval. Ultimately, to integrate the weighted layers, the fuzzy gamma operator and the geometric average method were applied. The normalized density index and prediction-area (P-A) plot were employed to evaluate the MPM models. The findings indicate that the developed models possess considerable validity and can be effectively utilized for planning future exploration endeavors.
M. Otari; R. Dabiri
Abstract
Heavy metal concentration in the soils and sediments has increased worldwide during the last century due to the mining, smelting, and industrial activities. The Forumad chromite deposit is located in the Sabzevar ophiolitic complex (SOC), with a long history of mining activities, yet very little is known ...
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Heavy metal concentration in the soils and sediments has increased worldwide during the last century due to the mining, smelting, and industrial activities. The Forumad chromite deposit is located in the Sabzevar ophiolitic complex (SOC), with a long history of mining activities, yet very little is known about the heavy metal contamination in its surrounding environment. In this research work, the soil pollution by heavy metals was investigated with respect to the geochemical, statistical, and environmental indicators over the chromite mine in Forumad. The concentrations of heavy metals were analyzed, and the results obtained showed that the mean concentrations of Cr (5837.5 ppm) and Ni (570.7 ppm) in the nearby soils and sediments were significantly high. On the other hand, the mean concentrations of the other heavy metals present such as As, Cd, Co, Cu, Pb, and V were close to the geological background values. The multivariate statistical analyses (Pearson coefficient analysis, Cluster analysis, and principal component analysis) were used to understand the various anthropogenic and geological (lithogenic) sources. Our geochemical and environmental assessments suggested that Cr, Ni, Co, and V had similar properties, and their presence in the soils was mainly from the ultramafic rocks and chromite deposits. However, the calculated enrichment factors for Cr and Ni were more than 10, suggesting their anthropogenic sources due to the mining activities. The significant Cr and Ni contaminations in the Forumad nearby soils indicated that the status of heavy metal contaminations of the area should receive further considerations in the metal mine areas throughout SOC.
