Some Observations on the Behavior of the Liquid and Gas Phases in Temperate Glacier Ice
Some Observations on the Behavior of the Liquid and Gas Phases in Temperate Glacier Ice
复制标题
关于温带冰川冰中液相和气相行为的一些观察
DOI：
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发表时间：
1975
影响因子：
3.4
通讯作者：
William D. Harrison
中科院分区：
文献类型：
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作者：
Charles F. Raymond;William D. Harrison
对取自蓝色冰川略低于平衡线至 60 m 深度的冰样本进行了显微镜和结构观察。收集后几分钟内就开始观察。在沿着三粒交叉点的静脉中、在晶界上的晶状体中以及在不规则形状中都发现了水。在晶体内部的气泡、接触静脉的气泡以及局部静脉中发现了气体。静脉大小显示出一定程度的扩散；平均横截面积约为 7 × 10−4 mm2，除表面 7 m 以内外，没有明显的纹理或深度趋势。在检查样本之前，它们可能经历了复杂的放松，这可能会显着改变它们。因此，无法确定静脉的原位尺寸，但可以确定上限。此外，无法预测单位面积的粒间水通量，但 1 × 10−1 m a−1 表示上限。在粗粒冰中，由于静脉密度低且被气泡阻塞，水通量密度可能更小。这表明，在典型的夏季，只有很小一部分融水能够以粒间尺度渗透到冰川中，除了可能在表面附近的情况。几个核心中存在类似管道的特征表明，许多融水仍然可以局部渗透冰，而不会沿着冰川表面进行大规模的横向运动。观察到的冰温分布表明，粒间水通量可能远小于根据岩心样品确定的上限。
Microscopic and textural observations were made on ice samples cored from Blue Glacier slightly below the equilibrium line to depths of 60 m. Observations were started within a few minutes after collection. Water was found in veins along three-grain intersections, in lenses on grain boundaries and in irregular shapes. Gas was found in bubbles in the interior of crystals, in bubbles touching veins, and locally in veins. Vein sizes showed some spread; average cross-sectional area was about 7 × 10−4 mm2 with no discernible, trend with texture or depth except within 7 m of the surface. Before the samples were examined they could have experienced a complex relaxation which could have changed them significantly. As a result it is not possible to determine the in situ size of veins, but an upper limit can be determined. Also it is not possible to predict intergranular water flux per unit area, but 1 × 10−1 m a−1 represents an upper limit. In coarse-grained ice the water flux density is likely to be even smaller, because of a low density of veins, and blocking by bubbles. This indicates that only a very small fraction of the melt-water production on a typical summer day can penetrate into the glacier on an intergranular scale except possibly near the surface. The existence of conduit-like features in several cores suggests that much melt water can nevertheless penetrate the ice locally without large-scale lateral movements along the glacier surface. The observed profile of ice temperature indicates that the intergranular water flux may be much smaller than the upper limit determined from the core samples.