Comprehensive Multi-Source remote sensing data integration for enhanced mineralization alteration extraction and geological structure interpretation in the Lala region of Sichuan Province

The Lala Copper Deposit, situated in the Kangdian Copper Belt, is a substantial copper reservoir. In recent years, extensive exploration for copper resources in the region has become critically important due to the growing demand for Lala copper deposit resources. Alteration minerals, serving as crucial indicators for prospecting, have not undergone systematic study regarding their spatial distribution and remote sensing geological structural features in the Iron Oxide-Copper-Gold (IOCG) type deposits of the Lala region. Multispectral and hyperspectral remote sensing data prove to be effective tools for exploring mineralization information. In this study, Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data and Principal Component Analysis (PCA) are utilized to extract the distribution of carbonate, iron oxides/hydroxide and quartz minerals. Gaofen-5 (GF-5) data and the Spectral Angle Mapper (SAM) method are applied to extract minerals such as albite, biotite, chlorite, hornblende and muscovite. Sentinel-2 data are employed for remote sensing geological structure interpretation in the Lala region. The results of remote sensing alteration anomaly extraction are validated through field verification, indoor spectral scanning analysis, and the calculation of the SID_SAM index. The mineralization alteration information extracted through remote sensing aligns well with field conditions upon verification. The SID_SAM indices for ASTER and GF-5 extraction results are 0.0272 and 0.0177, respectively, indicating a 35% improvement in GF-5 performance. This suggests that GF-5 hyperspectral data demonstrate superior capability in identifying alteration minerals compared to ASTER multispectral data. Finally, through a comprehensive analysis of remote sensing alteration minerals and structural features of known deposits, the study summarized the remote sensing geological exploration characteristics of IOCG-type deposits in the Lala copper deposit area. Seven new prospective areas for copper mineralization are ultimately identified. These research findings provide valuable references for the next exploration phase of similar deposits in the region.