New ASTER derived thermal indices to delineate mineralogy of different granitoids of an Archaean Craton and analysis of their potentials with reference to Ninomiya's indices for delineating quartz and mafic minerals of granitoids—An analysis in Dharwar Craton, India

Regional Lithological Mapping Using ASTER-TIR Data: Preliminary Case Study for the Tibetan Plateau and the Surrounding Area

“…The mixture of quartz and feldspar does not generally occur in sedimentary rocks, which suggests high QI functions well as an indicator of quartz-rich sedimentary rocks. The previous studies have confirmed that high QI is a distinct indicator for quartz-rich sedimentary rocks [14][15][16][17][18][19][21][22][23]26,29,30], and low QI is a distinct indicator primarily of sulfate minerals [15][16][17]30] and secondary of feldspar-rich silicate rocks [15,17,19,30]. The spectral emissivity of carbonate rock which is composed of the two major carbonate forming minerals on Earth, calcite and dolomite, is shown in Figure 3 (a).…”

“…As described above, high QI have been confirmed to be a distinct indicator for high-quartz / low-feldspar sedimentary rocks [14][15][16][17][18][19][21][22][23]26,29,30], but this study presents the first attempt to classify within the high QI rock bodies. The high QI (> 1.05) bodies are divided into three classes with the conditions on CI and MI.…”

“…Especially, Quartz Index (QI), Carbonate Index (CI) and Mafic Index (MI) defined for the ASTER-TIR data are finely analyzed theoretically and practically, and the performance of the indices in extracting geological information is confirmed [14]. Many studies have applied the indices (e.g., [13][14][15][16][17][18][19]) and other workers have proved the usefulness and stability of the indices in the local geological case studies (e.g., [20][21][22][23][24][25][26][27][28][29]). Despite ASTER radiance registered at the sensor data without atmospheric corrections applied are adopted for the calculation of the indices, the recognized scene dependency is quite weak if the atmospherically well conditioning data are selected [17].…”

Lithological and Hydrothermal Alteration Mapping of Epithermal, Porphyry and Tourmaline Breccia Districts in the Argentine Andes Using ASTER Imagery

“…Rockwell and Hofstra (2008) [71] applied QI and CI using ASTER Level-2 surface emissivity (Level-2B04) data to identify quartz and carbonates in northern Nevada, USA. Similar ASTER derived mineralogical indices using TIR data have been proposed to delineate quartz and mafic minerals contests for particular case studies (e.g., [72]). …”

Regional Lithological Mapping Using ASTER-TIR Data: Case Study for the Tibetan Plateau and the Surrounding Area

“…The mixture of quartz and feldspar does not generally occur in sedimentary rocks, which suggests high QI functions well as an indicator of quartz-rich sedimentary rocks. The previous studies have confirmed that high QI is a distinct indicator for quartz-rich sedimentary rocks [14][15][16][17][18][19][21][22][23]26,29,30], and low QI is a distinct indicator primarily of sulfate minerals [15][16][17]30] and secondarily of feldspar-rich silicate rocks [15,17,19,30]. The spectral emissivity of carbonate rock which is composed of the two major carbonate-forming minerals on Earth, calcite and dolomite, is shown in Figure 3a.…”