【摘要】 对东太平洋CC区(Clarion-Clipperton Zone)多金属结核丰度、品位、多波束地形测量、深拖光学覆盖率探测、地震勘探等一系列调查资料综合研究表明:①东区和西区结核在其化学成分和形态上有差异,但是聚类分析结果表明不能按区域断然分开;②因子分析得出东、西两区结核4种主因子是Mn组元素Mn、Cu、Ni、Zn,Fe组元素Fe、Co、Ti、Sr,岩源组元素Si、Al、K,生物元素Ca、P;③西区结核成矿物质主要来源于上覆海水中金属元素的化学沉淀,火山成矿作用使结核富集和丰度增加,趋势面和人工神经网络分析表明结核主要分布在海底坡度≤5°地区,该地区的结核量占总结核量的89.62％,坡度>5°地区结核量占10.38％;④东区结核丰度、覆盖率、地形三者变化一致,重大相变距离为10～15km,来自地幔成矿物质通过玄武质洋壳裂隙和断层,为多金属结核的形成和生长提供了丰富的物质来源,地球深部地质作用过程如基底岩浆房活动可能对结核分布产生重要影响;⑤东太平洋CC区多金属结核矿带的形成应归于海底板块扩张活动的一种资源效应和经后期表生地质作用改造的结果。更多还原

【Abstract】 The study areas are located in the western part of the Clarion-Clipperton Fracture Zone (CCZ) in the eastern Pacific. A series of geological and geophysical investigations, including measurement of abundance and grade of Polymetallic nodules and Seabeam topography, photography and coverage by the deep-tow television camera as well as seismic reflection, have been carried out during the past years. The integrated study revealed the following points. (1) There is a difference between the east district and the west district in chemical components and shapes of nodules, but the difference is not obvious based on the cluster analysis. (2) The factor analysis shows that the four element assemblages of polymetallic nodules are Mn, Cu, Ni; Zn, Fe, Co, Ti and Sr; Si, Al and K; and Ca and P. (3) In the west district, the material sources of nodules are mainly from chemical deposits of metal elements in the overlying water. Submarine volcanism increase the enrichment and abundance of the nodules. The nodules are mainly distributed in areas with slopes ≤5° (about 89. 62% of the total) and sesondarily in the areas with slopes >5°(about 10. 38%) according to the results of the trend analysis and artificial neural network analysis. (4)In the east district, the abundance, coverage and seafloor feature of the nodules are varied similarly with the significant distance of faicies change being 10-15 km. Metallic materials of the nodules are mainly derived from deep-seated mantle through openings of the basaltic oceanic crust and fault-s, which provide abundant materials for the formation and growth of the nodules. Gological processes such as activities of magma chambers should affect the distribution of nodules. (5)The formation of the polymetallic nodule belt in the CCZ is attributed to the effect of resources of plate tectonics and seafloor spreading, and the reworking of the late-stage supergene geological processes.更多还原