The discovered deep-buried lake ice in source region of the Huanghe River

Abstract

The 4.45 m-thick pure ice lens have been discovered firstly at depth from 19.81–24.26 m in the bore No.6, which locates in north bank of the Ngoring Lake. In source region of the Huanghe (Yellow) River,¹⁴C dating, X-ray diffraction, pollen analysis, micropalaeontology, chemical components, environmental isotope²H,³H,¹⁸O and freezing point of the ice and water samples from the bore have been tested and microorganism in the ice have been also appraised with microscope. Combined with the research on geomorphy and Quaternary around the lake, the ice lens are determined as a kind of deep-buried lake ice, formed in 35,030–45,209 yr.B.P., and annual mean air temperature was about −10°C during that time.