4315

4086

كارشناسي ارشد

اكتشاف معدن

اصفهان: دانشگاه صنعتي اصفهان، دانشكده معدن

1387

يازده، [101]،[II] ص.: مصور، جدول، نمودار

ص.ع. به: فارسي و انگليسي

نادر فتحيان پور،حسن طباطبايي

هوشنگ اسدي هاروني

1/11/87

جمال الدين خواجه الدين، احمدرضا مختاري

مهندسي معدن

ID4086

به فارسي و انگليسي: قابل رؤيت در نسخه ديجيتال

Abstract Based on regional geochemical prospecting using heavy mineral stream sampling in Hamadangeological rectangle area scale1 100000 a number of promising prospects for both metallicand non metallic ores were introduced Following this stage and through applying moredetailed litho geochemical and geophysical studies on the proposed area four anomalouszones were suggested for further exploration in more details The current study were definedin the same line of previous research to delineate more favorable areas in two better suitedanomalies in a GIS environment In order to to map different rock units and associated mineralization such as variousalterations ETM Plus and ASTER multi spectral images were employed After applyinggeometric radiometric corrections the data were smoothed and heavily vegetated area wereremoved for further preprocessing and enhancements routines The maximum likelihoodalgorithm was selected as the best multivariate supervised classifier for lithological mappingon preprocessed satellite imagery Using different methods of extracting alterations related to different types of mineralizations itwas found that the ASTER data was both spatially and spectrally superior for detectingalterations Principal component analysis least square fitting and band ratioing were foundmore suited for detecting Fe OH and Alunite bearing zones respectively In order to map geochmically anomalous zones a number of preprocessing methods such assorting validating estimating censored data and statistical analysis and visualizations throughhistogram charting were applied on rock and soil geochemical sample values Combinedmulti element maps were produced using multivariate partial correlation clustering and factoranalysis carried on elemental enrichment indexes Three different type of mineralization weredetermined based on type and intensity of multi elemental distributions called gold Cu Ni and Sb Pb The geophysical data including DC resistivity and magnetometric were modeled using 3Dalgorithms and the surficial physical properties were extracted from them through removingtopographic data and imported in GIS environment as evidential layers Using mineral potential mapping methods such as index overlaying weight of evidence andlogistic regression techniques three different favorability maps for Au Cu Ni and Sb Pbbearing zones were produced The inputted data layers for GIS integration were composed oflithologig maps Diroite Granite Gabbro and Aplite alteration maps OH Fe and Alunitebearing formations multiplicative geochemical elemts maps from rock samples Au S Ag Sb Cd Zn Pb Cu Ni Co and soil samples Sb Pb Cd Zn Cu Ni Cr Co geophysicalevidential layers true surface susceptibility and resitivity distributions plus faulting relatedlineaments In index overlaying method the weights were determined using our knowledge on the typeof different mineralization In assessing the final weight of evidence results the independency ofdifferent layers were evaluated via conditional independency tests For logistic regression method thefinal coefficients for each evidential layer were calculated and used in preparing the final favorabilitymap Overall evaluation of the maps produced from each method were through cross checking mapsshowed acceptable agreement and consistency

نادر فتحيان پور،حسن طباطبايي

هوشنگ اسدي هاروني

جمال الدين خواجه الدين، احمدرضا مختاري