| As one of the rapid development technology at the end of the 20th Century, application of remote sensing has penetrated in many aspects of society. The First earth source satellite named Landsat1 was launched in 1972 by USA, and from then on remote sensing have been introduced and developed in geologic survey. The combination of remote sensing and geology theory not only decreases the field's workload and the geological worker's labor intensity but also improves work efficiency and speeds up geologic survey.Reflection and emission data of ground objects are received by remote sensor by remote sensing platform and transported to the ground station. Each object has different special reflection spectra and the special reflection spectra are the main information recognized by remote sensing.Remarkable effect has achieved in exploration mineral resources using remote sensing alteration anomalies in Gobi desert. This paper studies Mengku-Abagong iron deposit belt which is low mountains and hills landform in Aletai, Xinjiang. The reflection spectra of rocks have been tested by ASD. Based on analyzing reflectance spectra, absorptive band assemblages give lots of information for remote sensing bands assemblage in extracting alteration remote sensing anomalies. Ascertaining spectral reflectance characteristics of altered minerals are the principle and basis for remote sensing information extraction.ASD is the abbreviation of advanced spectral device produced by USA using for the reflection spectra of rocks. The testing band range of ASD is 350-2500nm. Using PimaView3.1 to analysis reflection spectral curves and gain altered mineral assemblages. Mathematic integral method has been carried on the reflectance spectra and separately obtained the strong absorptive bands of remote sensing data. Analysis on the reflection spectral curves of Mengku's rocks and gain the main altered minerals include hornblende, actinolite , tremolite, chlorite, dolomite, calcite and montmorillonite, in addition biotite, halloysite, magnesite, siderite tourmaline and so on. Using the same method can gain the main altered minerals of Abagong's rocks mainly include phengite, illite, chlorite, actinolite, hornblende, halloysite, montmorillonite, calcite, nontronite and biotite. Mathematic integral method has been carried on the reflectance spectra and separately obtained the strong absorptive bands of two deposits of ASTER and ETM~+ data. Results are as follows:â‘ , the strong-middle absorptive bands of Mengku's rocks are band3, band8 of ASTER and band4, band 7 of ETM~+.â‘¡, the strong-middle absorptive bands of Abagong's rocks are band3, band6, band8 of ASTER and band4, band 7 of ETM~+.For verifying the veracity of ASD in statistical altered mineral assemblages, we did rock thin section analysis of some samples. Compare the two results and find that they are mostly similar. Considering that the treatment process of remote sensing data is statistical process, so the spectralresults are available.Remote sensing data is classified into multi-spectral and hyper-spectral on spectral resolution of optical remote sensing. Multi- spectral data such as ETM~+ and ASTER have been used in this paper. There are difficult in remote sensing information extraction of alteration anomalies because lower ground resolution of data, faint alteration anomalies information and the exiting of interference information. On the results of rocks' spectral curves, several methods have been used in extracting anomaly information corresponding geological background and the results are satisfactory. All the working area's alteration anomalies information is extracted on ETM~+ data. As a typical deposit, Mengku's anomalies information is also extracted on ASTER data. Anomalies information extracted in ASTER data is more similar to geological background than ETM~+ data for ASTER data's more bands and higher resolution. The technology in information extraction of alteration anomalies is relatively mature technology of "remove interference- abnormal major component- threshold classification". During July-August, 2007, partial anomalies information has been checked. It shows that the anomalies information verified the known deposits. More and more attention has been paid to remote sensing of being an effective method in mineral resource. Any geological exploration method has its adaptive conditions and limitation, so as to remote sensing. It is necessary to integrate RS information, geological information, aeromagnetiion and geochemical information on GIS platform. At last, we found some perspective areas from the anomalies information map. There are several prospectin targets in Mengku-Abagong iron zone. Three argets of type A and two argets of type B around Mengku and one argets of type A and two argets of type B around Abagong. The forecast areas are planed to be checked in 2008.
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