Lithological mapping of granitiods in the western Junggar from ASTER SWIR-TIR multispectral data: Case study in Karamay pluton, Xinjiang

Lithological mapping of granitoids is a hotspot in remote sensing petrology. In the western Junggar of northern Xinjiang, a number of granitic plutons are well exposed, and the lithological information is significant for the geological investigation of the western Junggar. In this study, the ASTER SWIR-TIR band ratios 13/12(R), 4/6(G) and (12 x 12)/(11 x 13) (B) false color composite imagery was proposed successfully to identify and extract alkali-feldspar granite, granite, granodiorite and monzogranite, respectively, based on analysis of the laboratory reflectance and emissivity spectra of Karamay granitiod samples measured by portable emission spectrometer and related minerals spectra from spectral library in the shortwave infrared (SWIR) to thermal infrared (TIR) region. The results show that ASTER SWIR-TIR multispectral data, especially TIR data, can be applied to map granitiods effectively. Furthermore, based on the Ethological and tectonic interpretation of ASTER imagery, mineral exploration prospect also infer around the II pluton and the interchange of between eastern I pluton and III pluton of Karamay, comparing with alteration features of the Baogutu porphyry copper-molybdenum deposit.