山东中部典型冰川岩溶的发现及气候意义

冰川岩溶为冰川融水对于下伏灰岩地层侵蚀形成的岩溶地貌,具有重要的气候意义,国内少有深入的研究。在山东费县小泉庄一带灰岩面上发现河曲状岩溶槽与冰臼一起构成的岩溶系统。对岩溶通道水流路径进行恢复,发现岩溶通道水流起源于前端的冰臼,根据岩溶通道的叠加关系恢复了通道形成的先后次序,进一步发现了冰臼具有位移特征,位移量的大小显示出移动过程具有稳定期与快速期。根据河曲状岩溶通道的特征及其与冰臼的关系,与阿尔卑斯山冰川岩溶特征进行对比,两者具有特征上的一致性。综合分析认为小泉庄灰岩面上分布的河曲状岩溶通道为冰水成因,其壶穴为冰水下注冲蚀形成的冰臼,均属于冰川岩溶。小泉庄典型冰川岩溶在中国东部低山丘陵区的发现,佐证了中国东部曾经存在广布的冰盖及山谷冰川。

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.