MACROSCOPIC AND MICROSCOPIC FEATURES OF THE QUATERNARY GLACIAL VESTIGES IN THE TANZHESI AREA OF THE WESTERN HILLS OF BEIJING

After a study of macroscopic features for the Quaternary glacial vestiges in the Tanzhesi area of the Western Hills of Beijing,the analysis of the appearances and assemblage features of quartz grain surface textures has been carried out for the palaeoglacial deposits of the Guantuoling and Zhaojiatai glaciations.The surface textures of quartz grains indicate a dominance of the appearance assemblage of glacial origin in the Guantuoling till and Dafuzhuang till of the Guantuoling glacial stage as well as in the Tainpingzhuang till of the Zhaojiatai glaciation,and glaciofluvial origin for the Lujiatan deposit of Zhaojiatai glaciation.Therefore,based on the macroscopic and micrioscopic features of the palaeoglacial vestiges in this area,it is certain that two palaeoglaciations had developed in the Early and Middle Pleistocene respectively.