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锑矿赋存于上寒武统博菜田组中段的硅质岩和硅化碳酸盐岩的层间破碎带中,矿化受区域上的北西向构造和地层所控制。深入研究,扩大资源和寻找新的资源基地。 相似文献
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Barberá C Fernández-Jover D López Jiménez JA González Silvera D Hinz H Moranta J 《Marine environmental research》2011,71(4):235-246
Irregular sea urchins such as the spatangoid Spatangus purpureus are important bioturbators that contribute to natural biogenic disturbance and the functioning of biogeochemical cycles in soft sediments. In the coastal waters of the Balearic Islands S. purpureus occurs in soft red algal beds, and can reach high densities. The diet of S. purpureus is unknown and it is particularly difficult to analyze the stomach contents of this group; therefore, we analyzed the fatty acid (FA) composition of the gonads and potential food resources in order to assess the trophic relationships of this species. The FA profiles of the gonads of S. purpureus agree well with the FA composition of the potential trophic resources (algae and sediment) and reveals changes between localities with different available resources. Three polyunsaturated FAs mainly contributes in the composition in the S. purpureus gonads: eicosapentaenoic acid (C20:5n-3) and arachidonic acid (C20:4n-6), both abundant in the macroalgal material, and palmitoleic acid (C16:1n-7), which is characteristic of sediment samples. Trophic markers of bacterial input and carnivorous feeding were significantly more abundant in sea urchins caught on bottoms with less vegetation. The current study demonstrates that the FA content of S. purpureus gonads is a useful marker of diet, as differences in the profiles reflected the variations in detritus composition. The results of this study show that this species has omnivorous feeding behavior; however, viewed in conjunction with available abundance data the results suggest that phytodetritus found within algal beds is an important carbon source for this species. 相似文献
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对阿莫锡矿床成矿地质背景、矿床地质特征、成矿流体的成分、酸碱度、硫逸度等物理化学条件的分析研究表明,阿莫锡矿床主要赋存于西盟群永龙组下段片岩和大黑山组上段变粒岩中,有明显的层控性质;成矿物质主要来源于隐伏花岗岩体;成矿流体由弱碱性向弱酸性演化,并经历了迁移、沸腾、沉淀的过程,显示多组分、高盐度、高矿化剂等特征.主要成矿阶段包裹体均一温度集中于380 ~430℃之间,成矿深度约3.9 km,流体密度为0.89 ~0.98g/cm3,流体盐度35%,矿床成因类型属于高温气成热液锡矿床. 相似文献
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Calcium and magnesium‐bearing sabugalite occurs as aggregations of yellowish platy crystals in veinlets or druses in conglomerate from the oxidized parts of the Tono uranium deposit, Central Japan. X‐ray powder diffractometry of this mineral has reflections consistent with previous powder diffraction data of sabugalite. It is included in the monoclinic system with space group C2/m and calculated cell parameters of a = 19.68Å, b = 9.89Å, c = 9.82Å α = γ = 90°, β‐96.93° and V = 1897.83Å3. Chemical analysis yields a formula of (Ca0.10 Mg0.09)Σ0.19Al0.53(UO2)2.04((PO4)1.99(AsO4)0.01)Σ2.00·11.22H2O. EMPA mapping shows that the mineral is compositionally uniform with no micron‐scale layering. Charge of cations including Ca and Mg in the cation‐H2O layer is 1.98 being identical to that of autunite group minerals. This suggests that the charge balance in the cation‐H2O layer of the mineral could be made by the alkaline earth or alkaline elements rather than by hydrogen ions. 相似文献