南沙群岛工程地质环境分区与质量评价

DIVISION AND QUALITATIVE EVALUATION OF ENGINNEERING GEOENVIRONMENT ON NANSHA ISLANDS

南沙群岛海区自然资源丰富 ,但工程地质条件复杂 ,地质灾害频繁。随着对该海区海洋资源的开发和其它海洋工程活动的增加 ,调查和研究其工程地质环境与质量评价就成为非常必要的前期工作。本文在分析了南沙群岛海区地质构造、活动断裂和火山地震活动的基础上 ,结合海洋水动力环境要素将南沙海区工程地质环境划分为 5个区 :南部陆架区、西部陆坡区、南沙海槽区、礼乐滩微陆块区、珊瑚礁隆起区 ,并深入分析了各分区的环境特征。本文还利用模糊数学的方法对南沙海区的工程地质环境质量进行综合评价分析 ,使评价结果更加客观合理 。

Nansha Islands have abundant natural resources , but there exist complex geoengineering conditions and frequent geological hazards.It is important and essential to survey and evaluate the engineering geoenvironment. On the basis of analyzing geological structure, active faults, volcanoes and earthquakes, and conbinination with the hydrodynamic conditions, the engineering geoenvironment in Nansha area is divided into 5 zones: southern continental shelf zone, western continental slope zone, Nansha trough zone, Liyuetan shoal zone and coral reef zone and the engineering-geological features in each zone are also analyzed . A fuzzy mathematic method is used to qualitatively assess the engineering geoenvironmental on Nansha Islands. the evaluation result is more objective and reasonable and provides a basis support of engineering geoenvironment for planning of resource development in Nansha Islands area.