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冰芯中的化学成分,记录了古环境和古气候的诸多信息,已有广泛研究.而冰芯剖面的物理特征,由冰芯形成时的水热条件和冰川运动变质作用所决定,同样记录了气候、环境和冰川运动的诸多信息.根据在乌鲁木齐河源1号冰川钻取的6根冰芯的详尽资料,结合冰流模式对冰芯冰龄的估算,分析研究了不同冰川带冰芯剖面的物理特征、形成机理和相应的水热条件.结果表明:积累区冰芯以粒雪-冰交替的原生沉积层为主,受冰川流动引起的动力变质作用影响较小,与该区成冰环境和冰川温度密切相关;平衡线附近的冰芯4.3 m以上主要是由渗浸冻结冰组成的原生沉积层,与附近的成冰环境相吻合,以下部分主要是经过动力变质作用的冰体,源于冰川上部的积累物;消融区冰芯主要由冰川上部下流的冰川冰组成,模拟显示该区冰芯冰龄较长,受局部成冰环境的影响很小.通过对不同区域冰芯特征比较,发现各成冰带的冰芯组成及污化层差别较大;在东、西支冰川同时期冰芯剖面的对比中,发现海拔相近点冰芯剖面组构相近,说明通过冰芯资料来探讨冰川内部特征以及该区域气候环境演变历史等较具代表性.
The chemical composition of the ice core, which records numerous paleoenvironmental and paleoclimate information, has been extensively studied, and the physical characteristics of the ice core profile are determined by the hydrothermal conditions and glacial movement metamorphism at the time of ice core formation, as well Climate, environment and glacier movement.According to the detailed data of 6 ice cores drilled in Glacier No 1 of Urumqi, combined with the estimation of ice core ice age by ice flow model, the ice core profiles of different glaciers The formation mechanism and the corresponding hydrothermal conditions.The results show that the ice core of the accumulation area is dominated by the primary sedimentary layer of the snow-ice alternation, which is less affected by the dynamic metamorphism caused by glacier flow, The environment and glacier temperature are closely related; the core 4.3 m above the equilibrium line is mainly composed of primary sediments infiltrated by freezing ice, which are in conformity with the ice-forming environment in the vicinity. The following parts are mainly ice bodies subjected to dynamic metamorphism, The ice cores in the ablation zone are mainly composed of glacial ice flowing down the upper part of the glacier. The simulation shows that ice cores in this area have a long ice age and are less affected by the local ice-forming environment. It is found that there is a great difference between ice core composition and the degree of contamination in each ice zone. In contrast with the ice core profiles of the same period in the East and West Sichuan glaciers, it is found that the ice cores near the elevation have a similar cross-sectional structure Ice core data to explore the internal characteristics of the glacier and climate evolution in the region more representative of the history.