中文摘要：

本文利用改进多谱图象分析方法，对实验获得的图象进行处理，获取不同时刻LNAPL含量差值（LNAPL Content Difference）在二雏空间上的分布图。通过图象分析探讨LNAPL在非饱和带中非均质条件下的迁移机制和分布特性。结果说明，介质的非均质性和流体特性对污染物的迁移产生重大影响；在“油-气”二相体系中，LNAPL含量差值分布呈现出较好的对称性，而在复杂的“水-油-气”三相体系中，LNAPL含量差值分布呈现出不对称性和非均匀性，这种不均匀性也反映了毛细带中含水量分布的不均匀性。

英文摘要：

The experimental pictures are processed by using the method of the reformed multispectral image analysis, and the distribution images of LNAPL content difference in two-dimensional space are obtained. Under the condition of heterogenons porous media the migration mechanism and distribution characteristics of LNAPL in unsaturated zone are discussed through the image analysis. The results indicate that the heterogenous and fluid characters of the media have great effects on migration of contamination. In the two-phase system with oil-gas, the distribution of LNAPL content difference shows the better symmetry characteristic, but in the complicated three- phase system with water-oil-gas, the distribution of LNAPL content difference shows the unsymmetry and uniformity characteristics which also reflect the uniformity of water content distribution in capillary zone.