第四纪冰川年代学以及新技术研究的现状、问题与趋势  

PROGRESSES, PROBLEMS AND STUDY TREND IN GEOCHRONOLOGY AND OTHER FIELDS OF QUATERNARY GLACIATIONS

作　　者：易朝路[1] Yi Chaolu(Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101)

机构地区：[1]中国科学院青藏高原研究所,北京100101

出　　处：《第四纪研究》2018年第3期537-561,共25页Quaternary Sciences

基　　金：国家自然科学基金项目（批准号：41230523）资助

摘　　要：一百多年来,新技术的运用和认识水平的不断提高,给第四纪冰川研究带来重大变化,研究方法和内容大致经历了两个阶段：早期的研究者采用野外地质地貌调查方法,定性描述冰川地貌和冰碛物沉积特征及其分布,根据冰川遗迹的相对位置和风化程度划分了4～6次经典冰期;20世纪80年代开始到21世纪初的近30年间,采用放射性碳、光释光和电子自旋共振、宇宙成因核素暴露年代,以及火山灰钾氩法/裂变径迹等测年技术测定冰川地貌及其相关沉积物的数值年代.其他新技术的不断涌现,定量化描述冰川遗迹,解决了许多以往第四纪冰川研究不能解决的问题,还发现了不少新的科学问题.结果表明：1）相当于深海氧同位素3阶段的大规模冰进、末次冰盛期（Last Glacial Maximum,简称LGM）、末次冰期早阶段的时代和倒数第二冰期的时代在全球范围内可以对比;北美洲、南美洲和青藏高原最老的冰期时代大约1 Ma.2）采用3S技术（GPS、GIS和RS）并结合野外调查,发现海洋性冰川作用区冰下磨蚀量与冰流速成2次方的定量关系,定量描述古冰川分布和平衡线的空间变化,最近和未来将采用数值模型并结合野外调查模拟山地冰川的面积、体积和平衡线等对气候变化的响应和反馈作用,并进一步提高实验室测年水平,对冰碛物精细测年,以利全球冰期对比和古冰川气候模拟.Major progresses in the study of Quaternary glaciations have been made as the newly developed techniques that are widely used over the last one hundred years.In the pioneer stage,researchers qualitatively described glacial landscapes and glacial sedimentary properties as well as their distribution in field using the strategy of geomorphology and sedimentology.4 to 6 traditional glaciations were divided based on the relative positions of moraines,glacial troughs,and the degrees of the weathering of glacial relicts and relevant glacial meltwater terraces.During the period of the 90s of the 20th century to the first ten years of the 21st century,researchers described and mapped glacial extent quantitatively using 3S techniques（GPS,GIS and RS）and combining specific field investigation,and dated moraines using radiocarbon dating,optically stimulated luminescence dating,electron spin resonance dating,cosmogenic nuclide surface exposure dating and tephrochronology.Based on these dating data and corresponding glacial extents,a global glaciation in the marine isotope stage 3 has been found,and glaciations occurred in the global Last Glaciation Maximum and the early stage of the Last Glacial period and the penultimate glaciation are also global events.The oldest glaciation occurred in 1 Ma in North America,South America and the Tibetan Plateau.At present and in the near future,simulation of response and the feedback of paleo-glaciers vs climate by using numerical modeling with combination of field demonstration will become a trend in the study of paleo-glacial area,paleo-volume and equilibrium line altitude,and refined dating techniques for moraine dating will be improved or developed for global comparison and simulation of Quaternary glaciations.

关 键 词：第四纪冰川 年代学 冰期对比 古冰川与气候变化 

分 类 号：P343.6[天文地球—水文科学] P597.3[天文地球—地球物理学]