摘要
首次发现鄂尔多斯地区发育有倒数第二次冰期冰楔假型，并根据此发现结合以往资料恢复了中国倒数第二次冰期多年冻土的边界，即105°E以东，118°E太行山一线以西地区的冻土南界在36°33’N附近，太行山以东地区位于40°20’N附近；而105°E以西的青藏高原地区多年冻土则分布在36°～29°N，现代海拔为2000-3100m的地区．边界附近倒数第二次冰期时的年均气温比现今要低10～15℃．
In this paper, the ice-wedge casts found in Erdos plateau were described in detail. As an evidence for reconstructing paleotemperature, periglacial geomorphological phenomena, ice-wedge casts were considered to be an important factor in paleoenvironmental research for a long period. From the TL dating and sediment analysis of the wedges, it is confirmed that the ice-wedge casts found in Erdos developed in the period of Penultimate Glaciation. According to the characteristics and the distribution of these ice-wedge casts, the permafrost boundary during the Penultimate Glaciation in China was reconstructed and the paleotemperatures on the boundary were estimated based on the correlative formulas among geographic factors. This boundary was divided into three parts; the east part, the middle part and the west part, respectively. Chiefly based on latitude, the east part of the boundary was located in the area east to 118° E and near 40°20＇ N, and the middle one between 105°E and 118° E and to 36°33r N southwards. Chiefly based on height, the west part was located at 2 000-3 100 m in the area west to 105° E. In addition, the mean annual air temperature of the entire boundary during the Penultimate Glaciation is estimated to be 10-5 ℃ lower than the temperature nowadays.
出处
《冰川冻土》
CSCD
北大核心
2008年第1期108-112,共5页
Journal of Glaciology and Geocryology
基金
国家重点基础研究发展计划(973计划)项目(2005CB422001)资助
