Application Study Of Remote Sensing Prospecting In Western, China

Dishui copper deposit in Baicheng and Duobuza porphyry copper-gold deposit inNgari, two typical deposits in xinjiang and Tibet respectively, were chosen for thestudy. In order to obtain the species and spectral characteristics of alteration mineralsin the two deposits, sample spectrum was tested firstly. After that, based on the ETM+and ASTER datum, remote sensing alteration anomalies were extracted inde-interfered anomalous principal component thresholding technique. Then,combined lithology and structure interpreted by remote sensing, remote sensingprospecting model for typical deposits was set up. Finally, field validation wasconducted to determine its feasibility.Through the analysis above, we gained several conclusions and knowledge in thearticle, they are made as follows:(1) There were strong absorption in band1、4、5、7and band1、3、4、5of ETM+data in alteration minerals in Baicheng copper deposit. And based on that, remotesensing alteration anomaly could be extracted through principal component analysis;There were strong absorption in band1、3、4、6and band1、3、4、8of ETM+datain alteration minerals in Baicheng copper deposit Duobuza porphyry copper-golddeposit. And remote sensing alteration anomaly could also be extracted according tothat.(2) Combined with remote sensing alteration anomaly, lithology as well asgeological structure, prospecting models were established in Dishui copper deposit inBaicheng and Duobuza porphyry copper-gold deposit. Abnormal alteration of ironstain and hydroxyl existed in prospecting models of Baicheng. However, an exceptioniron stain could not be an ore sandstone mark, but a mark for other metallic minerals.Hydroxyl alteration anomaly with a layered structure showed a banded-likedistribution; Ore-bearing rock formations were sandstone with zonal distribution andobvious stratification. The color of image was gray-green to yellow wax, withcorrugated features. The geological structure was simple with obvious zonal distribution, and its direction was consistent with the rock strike; Abnormal alterationof Al-OH and Mg-OH existed in prospecting models of Duobuza, and Al-OH was themain abnormal alteration. Abnormal alteration areas were in patchy distribution.Ore-bearing formations were mainly granite porphyry, they exposed in sheet shapeand had obvious alteration. The image color was fresh green. The complicatedgeological structure was in staggered distribution and had close relationship with thealteration rock. There were alteration rocks in internal structural framework orstructure line edge;(3) According to the remote sensing prospecting models, field validation in Kuqaand Duobuza were conducted. We found four copper deposit, two manganese depositsand two gold prospecting targets. Meanwhile, there were comparative copper reservesand reached a mineable size in Digangnamugang and Gaerqin, which had beenexplored by local geological enterprises. The field validation work showed that thetwo remote sensing prospecting models have a good applying value.