内蒙古中部地区古冰缘研究

A Study on Cryergic in Middle Inner Mongolia

在描述和分析内蒙古中部地区古冰缘基本特征的基础上,对砂多边形的成因、时代及反映的古环境进行了深入探讨,确认研究区内广泛发育的砂多边形为古冰楔。古冰楔可划分为两期,它们是末次冰期两个冰缘阶的产物,时代分别为距今36000～38000a和41000～45000a.古冰楔的存在说明研究区在末次冰期时处于严寒的冰缘环境中。

Based on describing and analyzing the general feature of fossil cryergic in the middle Inner Mongolia, the paper discusses the genesis, time of sand polygon and environments. Sand polygons, which exist broadly in the study area, are defmed as fossil ice wedge casts which can be divided into two groups belonging to two periglacial stages during the last glacial age. Their forming age respectively are 36000-38000 a B. P. and 41000-45000 a B. P.The exist-ence of fossil ice wedge casts indicates that the study area was located in the very cold periglacial environments during the last ice age.