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自生微球粒状石膏集合体和颗粒状石膏集合体被首次发现于东北太平洋水合物脊海区的两个沉积物钻孔SO143-221和SO143/TVG40-2中.X光粉晶衍射和电子探针分析表明,上述两种不同形态的集合体内矿物晶体均具有典型的石膏衍射峰和化学成分,其中主要化学组成略小于其他海区自生石膏.扫描电子显微镜分析显示,石膏呈清晰的单晶和双晶,清晰的晶体边界、晶面、晶棱和解理面.结合沉积物岩芯中已发现的与水合物伴生的自生碳酸盐岩和富含SO_4~2-和Ca2+离子的孔隙水,有理由认为这类石膏是自生形成于与水合物相关的沉积环境中,很可能形成于研究区富含SO_4~2-离子的海底水与下伏沉积物中甲烷水合物层之间的交互地段.自生的颗粒状石膏集合体和石膏微球粒集合体分别产自同一研究区不同的钻孔沉积物内,说明了两个钻孔位置处在不同的微地球化学动力环境.因此,这种特征性自生石膏可视作一种识别标志应用于其他海区,以确定其沉积环境是否与天然气水合物有关.
The spontaneous microspheres gypsum aggregates and granular gypsum aggregates were first found in two sediment SO143-221 and SO143 / TVG40-2 silts in the northeastern Pacific hydrate ridges, X-ray crystallography and electron probe The analysis shows that the above two kinds of mineral aggregates have typical gypsum diffraction peaks and chemical compositions, of which the main chemical composition is slightly less than that of other gypsum sponges. Scanning electron microscopy analysis shows that the gypsum has a clear single crystal and double crystal , Clear crystal boundary, crystal plane, crystal edge and cleavage plane.Combined with the hydrate-associated spontaneous carbonates and pore water enriched in SO 4 2- and Ca 2+ ions found in sedimentary cores, it is reasonable It is considered that this type of gypsum is formed spontaneously in the hydrate-related sedimentary environment and is likely to be formed in the interaction between the SO 4 2- ion-rich seafloor water and the methane hydrate layer in the underlying sediment in the study area. Of the granular gypsum aggregate and the gypsum microsphere aggregate were produced from different borehole sediments in the same study area respectively, indicating that the two borehole positions are in different micro-geochemical kinetic environments. Therefore, Be regarded as one kind of gypsum from the characteristic signature applied to other sea areas, to determine whether the depositional environment and gas hydrates.