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Using HyMap data, mineral identification and mineral mapping were conducted on the basis of the spectral absorption index (SAI) and other spectral absorption features in a study area in Tudun, eastern Tien Shan. Alteration minerals, such as calcite, alumina-rich (Al-rich) muscovite, epidote, and antigorite, were explored, and their relative abundance was depicted. A cross-validation was performed, and it showed a high degree of consistency between the imagery results and the results of previous literature. To further validate the mineral mapping from HyMap data, a field survey was carried out and rock samples were collected for quantitative analysis using a Por Infrared Mineral Analyzer (PIMA) and the software affiliated with it. Minerals were discriminated, and their relative abundance was calculated from the spectra. Although we found that the absorption band-depth and SAI agreed well with each other and with the relative abundance of mineral alterations, the spectral absorption band-depth provided a better representation. Finally, ore prospecting of the study area was presented, and we found the distribution and close spatial relationships among the minerals extracted using the HyMap data. In the northern and northwestern part of the Gold-mine area, there was a mineralized muscovite alteration showing a sheet or block distribution. In the Copper-mine area, Al-poor muscovite with a sheet distribution was distributed in the north and northeast region, and Al-rich muscovite showed a block distribution enclosed by the distribution area of Al-poor muscovite. These all showed good ore prospects for the study area. [ABSTRACT FROM AUTHOR]

Abstract: As the major water resource of the Tarim River, glaciers in the Tomor region have suffered major losses of ice in the last several decades. Based on topographic maps, high-resolution remote sensing image, field survey data and previous studies, changes of the six selected glaciers in the Tomor region (Qingbingtan Glacier No.72, Qingbingtan Glacier No.74, Keqikekuzibayi Glacier, Tomor Glacier, Keqikar Glacier and Qiongtailan Glacier) over the past ∼50 years were analyzed in this study. Analysis shows that all of the six glaciers showed continuous shrinkage. The reduction rate of Glacier No.72 (terminus retreat of 41 m a−1 and area loss of 21.5% during 1964–2009) was higher than the others, with a dramatically increased rate. This dramatic ice thinning, related glacier front retreat and area loss of the six glaciers, suggests that glaciers in the Tomor region might currently be suffering negative mass balance in response to the ongoing temperature rise. Differences in changes of the six glaciers are influenced by debris cover and other topographical factors. [Copyright &y& Elsevier]