Geochemische Untersuchungen an Moränen des Inylchek-Gletschers im Tien Shan

In this study, we present results of the chemical composition of the moraine cover from the Inylchek Glacier in Kyrgyzstan using observations from three field campaigns between 2010 and 2012. The sample locations were selected based on high-resolution remote sensing data. Sampling included the main profile from Lake Merzbacher to Station “Hochgebirgsobservatorium Gottfried Merzbacher”, which is about 8 km in length trending in N-S-direction. Chemical analyses of more than 60 elements, including Rare Earth Elements (an important tool for the discrimination and localisation of source areas of sediments, boulders and outcropping rocks) were carried out.
Based on these data different geochemical material streams have been identified. Generally, two chemical groups of sediments, the North Type/Lake Merzbacher and the South Type/Southern Inylchek can be distinguished. The Lake Merzbacher Type sediments are characterised by a uniform chemical composition, whereas the South Inylchek Type is geochemically more heterogeneous. Toxic elements in the sediments, such as Ni, As, Cd, Tl and U, are moderately enriched. The low sulphur concentration suggests that the main water transport is caused by suspended matter.
One erratic granite block was analysed for in situ cosmogenic ¹⁰Be for exposure age dating. The age of 330 ± 90 a is conform to a glacier high stand during the “Maunder“ minimum of the solar activity.