Discovery of glaciokarst in middle Shandong Province and its climatic significance

Glaciokarst is a kind of karst landform of limestone formed by the erosion of surface glacial melt water. It has great climatic significance despite there are few in-depth studies in China. In this research we found a karst system consisting of meandering karst grooves and glacial potholes on the limestone surface in the small village of Xiaoquanzhuang, Feixian, Shandong province. Based on the restoration of the water path of karst channels, it is found that the water flow in the karst channels was originated from the glacial potholes at the front end. Additionally, the time of the formation of channels was restored according to the superposition relationship of karst channels. The displacement features of glacial potholes and the displacement amount also suggest that the movement of glacial is featured by the alternation of stable and rapid stages. The features of the meandering karst channels and their relationship to glacial potholes in Xiaoquanzhuang are similar with those observed in Alps. Integrated analysis further suggests that the meandering shape of karst channels on limestone surface is formed by melt ice water as the potholes are caused by the erosion on the bottom of ice water, they are both typical glaciokarst landforms. The discovery of such a typical glaciokarst in Xiaoquanzhuang proves that ice sheets and valley glaciers was once widely spread in the low-hill region of East China.