Remote sensing information extraction of alteration anomalies in the Jiufang region,Yunnan,southwestern China: A case study

Remote sensing alteration anomalies information has been widely used and obtained good results in mineral exploration. However,it is very difficult to make the remote sensing information extraction of alteration anomalies due to complex topography and geomorphology and heavy surface coverage in southwestern China. Exemplified by the Jiufang region in Yunnan,the present paper deals with the main problems for the remote sensing information extraction of alteration anomalies in southwestern China, including the removal of interference information on the topographical and geomorphological features;the selection of the types of the remote sensing information extraction on the basis of geological background and metallogenic conditions,and the post-processing of abnormal information on the basis of existing geological data. The remote sensing anomalies in the Jiufang region appear dominantly in the southeastern part,and subordinately in the central and southwestern parts. The distribution of the remote sensing anomalies is found to be consistent with that of the geochemical anomalies,and associated with the fault distribution. The above-mentioned techniques are proven to be helpful to the improvement of the remote sensing information extraction associated with the mineralization in the local parts of southwestern China.