Asian Science Citation Index is committed to provide an authoritative, trusted and significant information by the coverage of the most important and influential journals to meet the needs of the global scientific community.  
ASCI Database
308-Lasani Town,
Sargodha Road,
Faisalabad, Pakistan
Fax: +92-41-8815544
Contact Via Web
 
Articles by R. Derakhshani
Total Records ( 9 ) for R. Derakhshani
  J. Rahnama Rad , R. Derakhshani , G. Farhoudi and H. Ghorbani
  The Arabian Platform containing the Zagros Mountain Ranges (ZMR) is located to the Northeast of the Arabian Shield. There are nearly 200 salt domes on the Arabian Platform. In the ZMR, structural anomalies are frequently associated with similar facies distribution patterns. In the eastern portion of the region, emergent salt plugs of Infra-Cambrian age exhibit the same alignment patterns. Such trends bear no apparent genetic relationship to the Tertiary folding responsible for the present Zagros fold belt but rather indicate their affinity with linear basement features which are readily observable on Landsat imagery and aerial photographs. Bending of anticlines in the competent cover rock, combined with minor strike-slip faults and horizontal displacements of parts of folded structures, strongly point to the presence of these basement faults. The salt plugs, which have pierced cover rocks of up to 10000 m thick, are distributed on the Arabian Platform along regional basement faults. The area of diapir outcrops is bounded by the Oman Line to the East and by the Kazerun Fault to the West. Pieces of the basement have been brought up to the surface on some of the salt domes. The fragments were transported by rotational ascent of the Hormuz Salt Formation to the present and former land surfaces. The recognition of features related to basement tectonic and realization of their implication in the control and modification of geological processes in an important adjunct to the search for hydrocarbon accumulations in this region. To our best knowledge, data of basement faults in the study area is scarce. Therefore, this study was carried out to determine basement faults and their relation to salt dome distribution. Considering the fold axis bending, the trend of the salt plugs and also the distribution of epicenters of the last century, numerous new basement faults are introduced in this study.
  R. Derakhshani and M. Abdolzadeh
  The goal of this study is focused on alteration, mineralization and geochemistry of Darrehzar porphyry copper deposit which is situated in the Central Iranian Tectono-Volcanic Belt. This deposit is associated with an Oligocene granodiorite stock which intruded Eocene Volcano-Sedimentary and Cretaceous carbonate rocks. Four distinct types of hypogene alterations are recognized at Darrehzar: Potassic, Phyllic, Argillic and Propylitic. Copper mineralization was accompanied mainly by phyllic and to a lesser extent potassic, alteration. In the potassic alteration zone, enrichment of K and depletion of Na, Ca, Mn and Fe took place. These changes attended replacement of plagioclase and amphibole by K-feldspar and biotite respectively. Potassic alteration was associated with a major addition of Cu, as evident from the occurrence of disseminated chalcopyrite and bornite in this zone. Phyllic alteration was accompanied by depletion of Na, K, Fe and Ba and enrichment of Si and Cu. Losses of Na, K and Fe reflect sericitization of alkali feldspar and destruction of ferromagnesian minerals. The addition of Si is consistent with widespread silicification, which is a major feature of phyllic alteration, as well as the addition of Cu mobilized from the potassic zone. Pertographic studies of this porphyry copper deposit indicate that granodiorite association is mainly composed of plagioclase, quartz, orthoclase, biotite, sericite. The main mineralization-related alteration episodes (potassic, phyllic, argillic, propylitic) have been studied in terms of mass transfer and element mobility during the hydrothermal evolution of the Darrehzar copper deposit.
  R. Derakhshani and M. Abdolzadeh
  Quantitatively evaluating of mass changes of major and minor elements that accompanied alteration in granodioritic rocks of Darrehzar porphyry copper deposit based on elements that were immobile during alteration is the aim of study that is done for the first time. Darrehzar porphyry copper deposit has four distinct types of hypogene alterations: Potassic, Phyllic, Argillic and Propylitic. Mineralogic study of these ore bodies distinguished an upper oxidation zone, an intermediate enriched zone and a primary sulfide zone. Copper mineralization was accompanied by both potassic and phyllic alterations. Supergene alteration was minor and restricted to a thin blanket of Cu sulfides under an argillic cap. Isocon plots illustrate that Al, Ti and Ga were relatively immobile during alteration and the mass was essentially conserved during alteration. At all stages in the evolution of the hydrothermal system, TiO2 and Al2O3 which are immobile and have a high correlation coefficient are used in the calculations. In the potassic alteration zone there is an obvious enrichment in K and depletion in Na, Ca, Mn and Fe. These changes were due to replacement of plagioclase and amphibole by K-feldspar and biotite, respectively. Potassic alteration was associated with a large increase in Cu represented by disseminated chalcopyrite and bornite in this zone. Phyllic alteration was accompanied by the depletion of Na, K, Fe and Ba and the enrichment of Si and Cu. The loss of Na, K and Fe reflects the sericitization of alkali feldspar and the destruction of ferromagnesian minerals. The addition of Si is consistent with widespread silicification which is a major feature of phyllic alteration and the addition Cu, mobilized from the potassic zone which is depleted in this element.
  R. Derakhshani and M. Alipour
  This study presents the results of a study on Acid Mine Drainage (AMD) resources and its remediation in Sarcheshmeh open pit mine, one of the world largest porphyry copper deposits in the southeastern of Iran. Water quality samples were taken from water resources around the Sarcheshmeh mine and from tailing decant water pond. Sarcheshmeh waste dumps are the most important AMD generating sources. Also, Sarcheshmeh tailings decant water acts as a neutralization agent for treating AMD and reduce AMD's metals. Due to the mixing of the tailing decant water with the AMD that reached Sarcheshmeh tailings decant pond by Shur River, Cu, Fe, Mn and Zn concentration reduce around to 99.9, 99.3, 95.9 and 88.92% respect to Shur rive, the source of heavy metals. The reduction ratio for metals is Cu>Fe>Ni>Mn>Zn>Pb>CD>Mg.
  R. Derakhshani , A. Mehrabi and Z. Baghfalaki
  The main goal of this study is determining of relationship between faults and copper potential in Chahargonbad area in Southern part of Central Iranian Volcanic Belt. This area has some of the known copper deposits in Kerman Province of Iran. Fault map of the area is prepared by studying of aerial photographs and after field checking of photogeological map of the region. Also, remotely sensed data from Landsat 7, helped us to provide a lineament map of the study area which was also controlled in the field for establishment of faults. Seventeen porphyry copper deposits in the study area are detected. These deposits are mapped, digitized and finally rasterized using GIS advantages. After digitizing and rasterizing of faults, some buffers are determined around them for measuring the situation of deposits within them. Then weight of evidence modeling is applied to quantify the spatial association between faults and porphyry copper deposits. Using remote sensing, GIS, weights of evidence modeling and field checking, it is recognized that porphyry copper deposits in Chahargonbad area, are concentrated through 1 km buffers around faults.
  M. Alipour and R. Derakhshani
  In this study for evaluating the irrigation return water, the ground water model was applied to the system. The model calibrated base on prepared conceptual model. Hydrogeological models are suffered from uncertainty and validation. Data scarcity and model calibration difficulties affect the model validation and reality. Due to differences in measurement and element scale of parameter values and variable, the errors associated with input data and boundary conditions and errors of measurement of observation variables, the model validation can't achieve by calibration. For defining all of the parameters, groundwater models need data. Reliability of ground-water model predictions typically depends on several parameters include the correctness of the conceptual model. This study shows the interaction between conceptual model and calibration. This study, relies on the actual situation, shows that the conceptual model could improve during model calibration step.
  R. Derakhshani and A. Mehrabi
  To provide guides for exploration of porphyry copper mineralization at a district scale, we examine the spatial association between known copper deposits and strike-slip faults/fractures in South central Iranian volcanic belt. Studying of aerial photographs and preparing of photogeological map of the study area, beside various image processing techniques, helped us to reveal faults/features of this area. Field reconnaissance and local detailed mapping followed to corroborate the evidence. The integration of remote sensing and field checking resulted in preparing geological map of the area. After converting the map to the raster one, buffers around the faults/fractures are extracted. Then the spatial associations between the porphyry copper deposits and strike-slip faults/fractures are quantified using weights of evidence modeling. The porphyry copper occurrences are associated spatially with strike slip faults/fractures within distances of 1 km. In addition, based on these observations local strike slip faults/fractures related to regional strike slip faults systems are the most important foci for emplacement of copper-bearing porphyritic intrusions in the study area. Taking advantages of GIS, remote sensing technology and weights of evidence modeling, it is detected that the most concentrated place of porphyry copper in southern part of central Iranian volcanic belt is among the faults/fractures and through 1 km around them.
  R. Derakhshani and A. Mehrabi
  In this study the theory of fuzzy sets is developed for geologically-constrained predictive mineral potential mapping. The application of the theory of fuzzy sets involves multi-class predictor patterns of geological features. Using the spatial association between known copper deposits and structural features of the study area which is provided by weights of evidence modeling, maps of fuzzy membership value for strike-slip fault fractures, batholithic pluton margins, pluton centroids, lithologic formations andhydrothermal alteration units are provided. After combination of these layers, zones of porphyry cupper potential are provided by using fuzzy gamma operator. This method for geologically-constrained predictive mineral potential mapping indicates that the predicted favorable zones for porphyry copper in the study area comprise 4 areas: good potential (0.35%), moderate potential (0.87%), weak potential (31.9%) and non potential for porphyry copper deposits (66.88%) where some well-known deposits like Meiduk and Sara are located in the favorable potential area. So, the application of the theory of fuzzy sets to mineral potential mapping provides a quantitative yet subjective technique for predicting mineral potential where a number of mineral deposits are known. Also, the application of the theory of fuzzy sets in the generation of geologically-constrained predictive maps of mineral potential can be useful to guide further exploration in the search for undiscovered mineral deposits in the study area.
  R. Derakhshani and A. Bazregar
  The effective solute transport parameters, longitudinal dispersivity (αx), transversal dispersivity (αy) and retardation factor (R) for a two-dimensional plume are estimated using time-concentration data of a sampling borehole through which the plume passes. The plume was produced by injection of 2 kg Uranine (Sodiumfluorescien; Color Index: 45350) in a borehole in uniform groundwater flow. Two-dimensional analytic equation of solute transport in a uniform groundwater flow was used to estimate the parameters. The results were compared with one well method of dispersivity estimation. A time-concentration curve was drawn using estimated parameters and compared with the observed time-concentration curve. Comparison shows the accuracy of the estimated parameters obtained by the former method. Based on the estimated parameters and the two-dimensional analytic equation the movement of the plume is predictable at any arbitrary time after injection for the study area. Based on the estimated parameters and the two-dimensional analytic equation the movement of the plume is predicted at 85 days after injection for the study area, where as it is shown in this study the predictable and observed concentration curve are exactly equal.
 
© All Rights Reserved Asian Science Citation Index