5930

5545

كارشناسي ارشد

اكتشاف معدن

اصفهان: دانشگاه صنعتي اصفهان، دانشكده معدن

1389

دوازده،88ص.: مصور،جدول،نمودار

ص.ع.به فارسي و انگليسي

احمدرضا مختاري، نادر فتحيان پور

هوشنگ اسدي هاروني

28/2/90

عبدالحميد انصاري، حسن طباطبائي

مهندسي معدن

ID5545

به فارسي و انگليسي: قابل رويت در نسخه ديجيتالي

Integration of Geophysical Modeling with Drilling Data in Chah Firoozeh Nowchoonand Seridoon Porphyry Copper Deposits in Order to Separate the High Grade Zones Student name Amin Sheikhzadeh Email address amin sh zadeh@gmail com Date of submission 2011 02 07 Department of Mining Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language Farsi Supervisor Dr Ahmadreza Mokhtari and Nader FathianpourAbstractAn obstacle in geophysical exploration of different types of metallic ore deposits especiallyporphyry copper deposits is misleading anomalism in geophysical cross sections which isnot related to economic zones of mineralization and frequently has intersected pyriticzones after drilling In order to characterize economic anomalism in geophysical sectionsafter inverse modeling this research has utilized discriminant function analysisincorporating IP RS lithology and alteration into a linear statistical model to predicteconomic zones in IP RS models In this study results of inverse geophysical modeling of IP RS data acquired fromChahfirouzeh Nowchoon and Seridoon are integrated with other drilling informationincluding Cu assays lithology and alteration logs in order to discriminate high grade zonesof commodity element Cu Available data for Chah firouzeh comprise two IP RS profilesand logging data of 26 boreholes four IP RS profiles over Nowchoon porphyry copperdeposit in addition to 23 drilled holes and two IP RS profiles and logging data of 5boreholes for Seridoon The research is founded employing linear discriminant functionanalysis in order to separate high grade zones of mineralization from low grade zonesbased on available exploration data Firstly inverse modeling is completed on IP RS data and 3D modeling has been continuedon lithological and alteration data surveyed from drilled holes Identical grids from IP RSmodels lithology and alteration models are extracted 5 by 5 m cells as an input todiscriminant function analysis over both of deposits Discrimination is firstly accomplished by only IP RS information which could not yieldacceptable results The alteration and lithological information were introduced to themodels as new independent variables which were dramatically improved the correctdiscrimination Linear discriminant model is characterized based on two and alsomulticlass different zones of copper grades but results have eventually demonstrated thatdiscrimination based on two classes 0 2 as cut off gives the best result It should bementioned that 75 of data are used for modeling and 25 are kept for model validation The statistical model developed for Chahfiroozeh yields 89 and 86 correctclassification for high grade and low grade zones respectively while the results forNowchoon has demonstrated 64 and 70 correct classification for high and low Cuconcentrations respectively This high percent of correct classification is mostly indebtedto introduction of lithological and alteration information to the model Correctclassification based on 25 of data used for validation is equal to 90 and 87 forabove and below cut off respectively for Chahfiroozh and 64 and 70 for Nowchoon Keywords Porphyry Copper Nowchoon Chah Frioozeh Seridoon Discriminant FunctionAnalysis IP RS data

احمدرضا مختاري، نادر فتحيان پور

هوشنگ اسدي هاروني

عبدالحميد انصاري، حسن طباطبائي