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The study area is located in the middle section of Andean metallogenic zone. Excellent mineralization geological
conditions make it the most principal Porphyry Copper Deposits (PCDs) distribution area in southern Peru and there are
several super-large PCDs for hundreds of kilometers in every direction. The regional metallogenic regularity of this area
is controlled by the NNW fault parallel to the trench on the west of the South American continent. Small porphyry rocks
are very common in this area (circular structure pattern in remote sensing image) with typical zoned alteration of PCD -
potassic alteration, argillic alteration, phyllic alteration and propylitization (most exposed) from inside to the outside on
the surface. These geologic features can be recognized and extracted by using remote sensing image data. Accordingly,
the reflectivity curve of main altered minerals of the typical alteration zones of PCD was rebuilt which was corresponded
to B1-B9 of ASTER satellite data, based on the altered mineral assemblages and their spectral characteristics of the
typical alteration zones of PCD, and ASTER data’s ability of identifying minerals with argillic alteration and carbonatite
alteration. Based on the standard spectral data of USGS, We found that the information of argillic-and phyllic- altered
minerals assemblages in the typical alteration zones can be extracted in the principal components analysis pattern based
on ASTER B1467 while the information of propylitization altered minerals in the principal components analysis pattern
based on ASTER B1348 with larger reflectivity of B9 than B8, after comparing and analyzing comprehensively the
spectral curve characteristics of main altered minerals. In this method, altered minerals assemblages of argillic-and
phyllic- altered zone and propylitization altered zone in this study area was extracted, and the results agree well with the
distribution of known PCD. Meanwhile, remote sensing geological interpretation has been carried out by using
man-machine interactive remote sensing interpretation technology, and then in connection with the metallogenic
geological characteristics, the mine indicating information such as ore-controlling structure, source rocks and ore-hosted
rocks of PCD were achieved in the study area. Finally, a comprehensive assessment for mineral exploration by remote
sensing in the study area is accomplished and five favorable area for mineral exploration by remote sensing is delineated,
based on the remote sensing mine-indicating information such as linear and circular-shaped ore-controlling structures,
source rocks and ore-hosted rocks, argillic-and phyllic- altered and propylitization altered minerals assemblages.
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