College of Geo-exploration Science and Technology，Jilin University，Changchun 130026，China

Aiming at the two typical iron ores in South America (Superior type and Algoma type)，iron oxide alteration and hydroxyl alteration information have been extracted from ETM + data using spectral angle mapping (SAM) method． The authors conducted the information of host strata and ore- controlling structure by image en- hancement and false color composite combined with manual interpretation． The rules and characteristics of ore infor- mation were analyzed and remote sensing ore- prospecting model was established． Through the synthetical study of the remote sensing model，two promising mineral areas were predicted and the scope of geological survey was nar- rowed．