COMBINING REMOTE SENSING AND PETROLOGY DATA IN THE NORTH QIADAM UHP TERRANE, CHINA

ASTER images collected of the Qaidam basin in northern Tibet show exposures of ultra-high-pressure (UHP) metamorphic rocks interfolded with an ophiolite sequence. These units are both thought to be large bodies of consistent age formed by a single tectonic event, with a genetic relationship proposed to exist between them. However, this is still speculative due to a lack of detailed geologic data and mapping in these remote areas of Tibet. Using ASTER imagery and spectral properties, more data about the potential genetic link between these exposures can be obtained. Four localities along the north Qaidam margin were examined; Dulan Shan, Xitie Shan, Luliang Shan, and Qing Shan. Specific focus was placed on Luliang Shan, as fieldwork done in that area provided a detailed field map and petrologic samples of the rock units to us as a comparison to spectral data. These rock units were spectrally analyzed with bandwidth ratios and band-math, then compared with the field samples to confirm where the different rock units were present and what factors caused the distinct contacts visible in the ASTER images. Isolating the factors that distinguished between the UHP metamorphics, granitic intrusions, and the Ophiolite sequence in the ASTER imagery could allow these factors to be applied to imagery of other remote areas in the Himalayas, providing geologic data without needing to reach these areas to do fieldwork.