【作者】 吕华华；

【导师】 李乃胜； 石学法；

【作者基本信息】 中国科学院研究生院（海洋研究所） ， 海洋地质， 2005， 博士

【摘要】 本文利用沉积物涂片、X 射线衍射、红外光谱、地球化学、电子显微镜等分析手段对赤道北太平洋粘土沉积物进行了综合研究,阐明了研究区内沉积物类型、分布特征、矿物组成、元素分配及其制约因素,发现研究区内粘土矿物主要来自陆源,同时不同程度地含有火山、生物组分,其分布格局受构造活动、地形、水深、大气环流、洋流、物质生产力等要素综合控制。与地表粘土相比,研究区粘土的结晶程度差、活性好、吸水率高、有机质、氧化铁等致色杂质含量高。沉积物中还存在大量伊/蒙混层矿物,混层结构中蒙皂石层含量较伊利石层高,这种结构特征决定了研究区大洋粘土的物性优于地表同类粘土。为了探索大洋粘土应用中必须解决的提纯、增白和改性问题,设计完成了一系列对比实验,总结出最佳处理工艺为风干制浆提纯、酸溶氢气还原法漂白、干法和湿法改性。研究结果表明,处理后的粘土结构中层状框架基本保持完好,物性等级明显提高,在建材、冶金、机械、化工、医药等领域有着良好的潜在应用前景。 论文的主要创新之处在于首次获得了区内粘土沉积物的热释光标型特征,发现它可能是深海沉积环境和物质来源的有效替代指标;并且成功地对大洋粘土沉积物进行了改性实验,使其物性改善、可应用性提高。更多还原

【Abstract】 Integrated studies were carried out on the clay sediments from the Northern Equatorial Pacific by means of Sediment Slides, X-ray Diffraction, Infrared Spectrometry, Geochemistry Analyses and Transmission Electron Microscope. From the sedimentary types, clay mineral composition, crystal structure and distribution patterns, element composition and thermoluminescence characteristics of the sediments in the studied area, it can be told that the major sources of clay sediments were terrigenous detritus, volcanism and biological activity also made a contribution in some cases. The deposit patterns were controlled by the tectonic effect, marine palaeoenvironment, bottom topography, water depth, surface, intermediate and deep water circulation, atmospheric circulation, and palaeoproductivity together. Compared with the similar clay minerals on the land, those in the pelagic sediments were poorly crystallized, they had smaller particles, higher absorption and cation exchange capacity, and contained more impurities, such as organic compounds, ferric oxide, et al., which caused the deep color of sediments. Another significant feature of pelagic sediments was a lot of mixed-layer minerals, mainly illite/ smectite (I/S) presented. In the structure of I/S, smectite sheets had a larger number than illite sheets, which caused that clay minerals in the studied area had an advanced properties than those on the land. Contrastive experiments were designed to purify, whiten and improve the components of the clay sediments, by far the best solution were drying-serum purifying, acid and Zn reaction removing, powder and medium dissolution ion exchange improving. Structure analyzes had shown that white clays after treatment were little altered in the crystal lattice, but undoubtedly promoting the degree of the chemical and physical capacity, which promise a potential use in various industrial applications, such as production of ceramics, paper, pigments, architectural materials and ores smelts. The author investigated the typical thermoluminescence characteristics of the pelagic sediments in a creative way, and found it can be used as proxies for the sedimentary environments and mineral sources. The perfect results of purifying, removing and improving experiments encouraged the industrial application of ocean clay minerals in the future.更多还原