大凌河口附近海冰的内部结构分析

Inner structural study of sea ice in Dalinghe River estuary region

在中高纬度水域,近海与海洋生产建设不可避免的要遭遇冰的影响,尤其在冬季。因此,认真研究海冰的基本物理性质和本构特征尤为重要。对取自大凌河口的两根海冰冰样进行分析,沿厚度连续地自上而下竖直切片,并且等间距地水平切片,在正交偏光镜下观测冰晶结构;同时测量了每个样本不同位置的密度、盐度和含泥量以及分析其孔隙率;最后探讨了这些物理量之间的关系。结果得到:冰样上层为颗粒状晶体,中下层为柱状晶体;气泡多为球形,百分含量较低;冰密度在860～930kg/m3之间,盐度随深度呈C字型变化。

In the middle and high latitude regions,offshore and marine production and construction are inevitably subjected to ice load,especially in winter.Therefore,it is vital to study earnestly the basic physical properties and construction characteristics of sea ice.In this paper,two natural sea ice samples,derived from Dalinghe River estuary area,were vertically sliced continuously and horizontally sliced with equal spacing into thin sections according to the length brought about when taking samples.Putting the thin sections under the Universal Stage（a polarized light mirror structure）,we observed the crystal structures of sea ice.Densities,salinities and air bubbles in different parts of samples were measured as well as the amounts of mud contained,and the relationship among these physical amounts were discussed.Results have been obtained as follows：the upper layer is grained crystal;the lower-middle layer is prismatic crystal;the bubbles in ice present spherical shape and have a low percentage concentration;the ice density varies between 860 and 930 kg/m3 and the salinity presents a C-shaped curve against depth.