Extracting Remote Sensing Anomaly Information Of Alteration Based On ERDAS

At present,as China's rapid economic development,the supply and demand of mineral resources in the growing contradictions.whareas deposits is decreased year after year,and some minerals which had now easily been find before,such as outcropping mineral,light mineral,large mineral,and so on,are decreased too.It is clear that we might as well earlier find the solution of rasource exploration and deposit study,which should be an effective, rapid and exact technology,used it to carry out metallogenic prognosis.Recently,remote sensing exploration developed quickly,Thus,the abnormal information of ETM alterative remote sensing is the technology which can quickly recover mostly area in short-term,identify and extract mineralization Information.Now that the technology is the most efficient measure,if make use of it,we can quickly realize large mineral forecast and confirm the strategy zone of large mineral lands,but there also have some main problems presently,such as the mineralized alterative Information is faint,obstacle factors given by man ore much,and there are larger non-mineralized alteration in extracting alterative abnormal information.The paper came from wall rock alteration,which is the direct signal of mineral foundation,then,made use of ETM+ to extract the remote sensing abnormal information of mineralized alteration in the sands and desert area,and,matched the detail geologic data explanation to eliminate or weaken the disturb by the remote sensing information of non-mineralized,also discussed the employment of region about the remote sensing information of alteration.The paper began whir basic principle of remote sensing and technology,summarized the relation between hydrothermal solution wall rock type of alteration,alterative type,between alterative type and mineral products.Approved that the alterative rock information and metallic ore deposit has high relativity,searched the spectrum characters of all kinds of alterative rocks in band of ETM+ image.Last,summarized spectrum,which has judging sense,in visible light-near-infrared,is produced by Fe²⁺,Fe³⁺ and OH^-,H₂O,CO₃^2-. Based on the theory foundation of the remote sensing Information of mineralized alteration and region geologic foundation,by contrast different experimentation,the paper summarized the best way,which is principal contamination Anomaly +Ratio Law,use the method,we extract ratio alterative abnormal information in ya'ershabulake,and develop the field check,at last In mapgis6.5,I integrated the geological mineral deposit map,and analyzed synthetically spacious teams between the alterative abnormal Information and stratum, structure,rock body,mineral deposit.Then linking geologic mineral data,1 given three ore -finding targets.In a word,the paper thought alterative abnormal information can be an independent ore-finding signal.That is to say,the extracting alterative abnormal Information,which is given by "ETM+ image",has many advantages,to illustrate:rapid,economical,large area processed and few obstacle factors which by man,it can rapidly realize exploration or confirm metallogenic distant Zoo.