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1.
Adsorption isotherms and UV-visible and Mossbauer spectroscopic data point to specific interactions between flavomononucleotide (FMN) and Fe(3+)-smectite. The maximum amount of FMN adsorption was 0.3 mmole/g of Fe(3+)-smectite giving a 1:1 molar proportion of Fe3+ and FMN. The results suggest a Fe(3+)-FMN complex residing at the smectite surface. Other homoionic smectites (Cu2+, Zn2+, and Ca2+) exhibited lower levels of adsorption and less apparent specific interaction.  相似文献   

2.
Results of the experimental study of ion exchange properties of deep-sea pelagic sediments and related ferromanganese nodules (FMN) are considered. The exchange complex of sediments and nodules includes Na+, K+, Ca2+, and Mg2+ cations. The FMNs also include Mn2+ cations. Series of reactivity of metal cations during exchange reactions in different types of pelagic clayey sediments and diagenetic-sedimentary FMN are compiled. Series of exchange capacity of the sediments and FMN for alkali and heavy metal cations are also presented. The exchange capacity of FMN is always higher than that of enclosing sediments. Sediments are characterized by reversible equivalent sorption of cations of both alkali and heavy metals. Irrespective of the mineral composition, the FMNs are characterized by the reversible equivalent sorption of alkali metal cations, whereas sorption of heavy metal cations is only partly reversible. More over, alkali metal cations do not replace heavy metal cations. The results obtained refine the role of ion exchange processes in the redistribution of heavy metal cations at the water-bottom sediment interface during the diagenetic-sedimentary formation of ferromanganese nodules.  相似文献   

3.
A complex study of oceanic ferromanganese nodules (FMN) from the abyssal Clarion-Clipperton Fracture Zone and Lamont Guyot (Pacific Ocean) is performed. The concentrations of noble and trace elements are determined by AAS, INAA, and RFA-SR. Furthermore, SEM, and activation autoradiography are applied. Experiments are carried out using Pt, Au, and Ir radionuclides (radioisotope indicator method).  相似文献   

4.
大洋多金属结核资源评价的基本理论与方法   总被引:2,自引:0,他引:2  
根据大量工作实践和研究,系统扼要地介绍了大洋多金属结核资源评价的基本概念、理论基础、评价方法及国内外概况;论述了多元统计分析 (聚类分析、因子分析、趋势面分析 )、地质统计学 (克立格法 )、神经元网络分析进行多金属结核资源评价的方法原理;以及实现矿区边界指标-资源量-面积动态分析的《大洋多金属结核资源动态评价系统》软件开发简介.  相似文献   

5.
Results of the study of shallow-water ferromanganese nodules in the Gulf of Finland of the Baltic Sea, which are of practical interest for metallurgical and chemical industries, are discussed. The nodules contain the following elements: Mn, Fe, Si, Al, Na, Mg, Ti, K, V, Cu, Ni, Zn, P, and Ba. Contents of Mn (~30%) and Fe (~10%) are virtually similar to those in deep-sea oceanic nodules. However, concentrations of Ti, Cu, and Ni are notably lower than average values in oceanic nodules. The helium isotopic composition was studied to reveal cosmic dust in the nodule substance. The measured 3He and 4He concentrations are ~10?12 and ~10?5 cm3/g, respectively. The isotope ratio 3He/4He is approximately 10?7. More than 60% 3He is of cosmic (solar) origin, whereas 4He is of terrigenous (radiogenic) origin. Based on the cosmic duct concentration and the space tracer method, the FMN growth rate is estimated at 8–9 mm/ka at the nodule age varying from ~800 to 1500 yr. The growth rate of nodule has negative correlation with its size. Based on literature data, the growth rate of FMN from the western Baltic Sea is twice as high. An independent calculation of the FMN growth rate based on the diffusion-sorption mechanism (DSM) yielded 8.1 mm/ka, which is very close to the result based on the space tracer method. This value is proposed as the average growth rate of the studied nodules. Comparison with our previous measurements of growth rates for oceanic nodules showed that these values differ only slightly and are equal to n mm/ka, where n < 10. It is inferred that the formation mechanism of both marine and oceanic nodules is based on the same principles that control the generation of mobile forms of Mn in the bottom layer of sediments, i.e., principles related to bioproductivity of sea and ocean basins. Fluxes of lithogenic forms of Mn are of minor importance.  相似文献   

6.
张富元  沈华梯 《沉积学报》1997,15(3):126-132
本文对太平洋CC区(Clarion-ChppetonZone)多金属结核富集区的结核丰度、品位(Mn、Cu、Co、Ni)进行了详细的地质统计学分析、获得了较好的实验变差图。分析结果表明光滑型结核富集区的丰度变程为50~60km,结核水平分布连续性好,丰度稳定而变化小,结核中Mn、Cu、Co、Ni四种金属元素变程为80~100km,各向异性和空穴效应现象不明显;粗糙型结核富集区丰度变程为40~50km,结核中Co、Ni、Mn变差图拟合较困难,它们的变程约100km,大多数变差图形表现出有漂移、穴穴效应和各向异性现象,结合其它实际调查资料分析,影响变差函数稳健性的主要因素是粗糙型结核贫富分布不均且变化大。克立格法和算术平均法两种方法计算得出的结核资源量误差一般为1%~2%。最大误差不超过7%,这与以往的分析结果基本一致。研究结果表明,结核丰度采样间距为28km×28km,结核资源估计误差:光滑型结核区为29.45%的资源估计误差下降到14.59%,粗糙型结核区为36.07%;采样间距缩小到13km×13km,光滑型结核区的资源估计误差下降到14.59%,而粗造型结核区资源估计误差仍有23.01%。  相似文献   

7.
拉曼光谱是一种快速无损的分析手段,它既可观察样品的显微结构构造,也可分析样品的成分和结构。为了丰富多金属结核的岩石矿物学特征,文章对西太平洋某海山区的多金属结核样品进行了X射线粉末衍射分析和拉曼光谱分析。X射线分析结果显示该区域样品主要含有水羟锰矿、钡镁锰矿、斜长石、钙十字沸石和石英,显微构造主要有纹层状构造、柱状构造、树枝状构造、充填构造等。通过分析对比潮湿样品和烘干样品铁锰质矿物的拉曼特征谱峰,得出结核中水羟锰矿的特征谱峰位于490 cm~(-1)、570 cm~(-1)和626 cm~(-1)附近,钡镁锰矿的特征谱峰则位于640 cm~(-1)附近,与陆地上对应矿物的特征拉曼谱峰不同。结核中的钡镁锰矿结构不稳定,经过风干或者抛磨后部分产生相变,不同显微结构中,相变情况不同。经与RRUFF数据库比对,识别出钙十字沸石、斜长石等自形晶,多分布于结核最内层,往结核外层总体减少。矿物微晶多见铁锰质矿物微晶和钙十字沸石微晶,铁锰质矿物绕其向外生长。  相似文献   

8.
通过对MAPGIS进行二次开发,针对大洋多金属结核矿产资源评价特点,研制开发了大洋多金属结核资源评价管理系统。该系统由工程管理、专题图件编辑、空间分析、查询分析、属性分析、数据模型等功能模块组成,实现了对大洋多金属结核空间数据进行管理、统计分析、成图显示、矿区圈定、资源量计算等功能,为大洋多金属结核资源评价提供了实用有效的手段。  相似文献   

9.
大洋多金属结核同位素地球化学研究   总被引:1,自引:0,他引:1  
刘淑琴  宋鹤彬 《地球学报》2000,21(3):273-281
本文对DY85-1航次采自东太平洋海盆“CC”区不同地貌区、不同类型的大洋多金属结核进行了O、C、H、Si等同位素综合研究。结果表明,O同位素变化能反映结核的生成环境、生长速率、物质来源及成矿机理;Si同位素组成特征能帮助推测结核核心物质的来源;C同位素的研究表明,多金属结核成矿作用是在古海洋水变冷的总趋势下进行的;δ13C、δ18O和δD的规律变化,反映了海洋水变冷的周期性和渐变性。  相似文献   

10.
陈锦  白志民 《矿物岩石》2007,27(2):116-120
实验以大洋多金属结核浸出渣(66%,质量分数)为主要原料、高岭土(21%)为粘结剂、蛭石(13%)为膨胀剂,研制出用于动态吸附废水中重金属离子的浸出渣颗粒。以造粒后的颗粒为吸附剂动态处理含Cu2 的模拟废水,研究发现溶液浓度、流速、pH值对动态吸附效果的影响,选定浸出渣颗粒动态处理重金属废水的工艺参数:造粒后浸出渣颗粒的比表面积为18.61 m2/g,当模拟废水中Cu2 溶液的初始浓度为27 mg/L、pH=5.35、出口流速为10 ml/h时,每克浸出渣颗粒可动态处理模拟废水114.3 ml,处理后溶液中阳离子的浓度≤0.5 mg/L,实验效果明显。  相似文献   

11.
Carbonate nodules have been encountered for many years in the southern Illinois Basin, in parts of southern Illinois, southern Indiana, and southwestern Kentucky. The nodules occur as oblate spheroids of calcium carbonate that are isolated in the shale immediate roof of coal mines. They are common in the Springfield coal seam, known as the No. 5 seam in Illinois, and as the No. 9 seam in western Kentucky. Several different mechanisms have been proposed for the formation of various semi-spherical objects in coal measure rocks. The distribution and association with rooted horizons suggest that carbonate nodules in black fossiliferous shale observed in the roof of a studied mine in the Springfield seam represent pedogenic carbonate paleosols, which formed in a caliche-favoring environment subsequent to Springfield mire deposition. This interpretation is supported by 87Sr/86Sr isotope ratios of 0.710893 ± 13 to 0.711035 ± 12, which indicate a freshwater rather than seawater source.Petrographic examination of rock textures and mineral grains indicates that nodules collected from two Illinois Basin coal mines are composed of subangular grains of fine-grained, crystalline microspar. Although the carbonate is not ferroan, iron hydroxide stains interstices between microspar grains. The rounded, commonly pinched boundaries of nodules truncate commonly imbricated microspar grains. In contrast, concentric growth patterns are not observed except as defined by secondary, subhedral to euhedral pyrite crystals that form a diffuse, concentric replacement zone around the nodule's outer rind. Polished slickensides, with well-developed radial slickenlines, are developed at highly compacted margins in black shale or mudstone that commonly encases the carbonate nodules.Of the 450 carbonate nodules documented at a study mine in the southern Illinois Basin, the long axes of 36% are preferentially aligned parallel to regional structures such as anticline axes and drag folds that are interpreted to have formed in response to compression during the Late Pennsylvanian-Permian Alleghanian orogeny. Mapping also suggests that clusters of carbonate nodules are spatially associated with the trends of low-angle drag folds in the immediate roof of the Springfield seam at the study mine. The preferential elongation and distribution with respect to tectonic structures suggest that regional compression influenced the shape and distribution of carbonate nodules, and that nodule lithification may have been approximately contemporaneous with regional deformation.  相似文献   

12.
王征  朱茂旭  周良勇 《矿物学报》2007,27(2):131-136
利用锰氧化物具有高的吸附与氧化还原化学活性的特点,研究了采自东太平洋的铁锰结核对阳离子染料次甲基蓝氧化性脱色特征。结果表明,铁锰结核表面的非均相氧化是次甲基蓝脱色的主要机制。在通常的染料废水浓度范围内,铁锰结核可有效地对次甲基蓝染料废水氧化脱色。随染料浓度降低,铁锰结核投放量增加和粒度减小,次甲基蓝的脱色率明显提高。次甲基蓝的矿化程度(TOC去除率)较高,但仍低于脱色率。pH对次甲基蓝脱色的影响主要体现在对表面配位体形成和对体系还原电位的影响,当pH<4.0时,脱色率随酸度的增加明显提高;当pH在4.0~10.0时,溶液pH值对脱色率影响有限。在铁锰结核连续循环体系中,溶解Mn2 浓度和pH的增加是脱色率不断下降的主要原因。  相似文献   

13.
Cauliflower-shaped nodules are widespread in a single red mudstone bed in the Buntsandstein (Triassic) facies of the Iberian Range. They consist mostly of quartz, dolomite and calcite, but other minerals, such as barite, kaolinite and iron oxyhydroxides, are also present. The nodules are spherical, ovoid or elongate in shape and range from 1 to 8 cm across. The surface of the nodules is irregular, and some show a pedogenic coating of microspar. The sedimentological and petrographic data suggest that the initial anhydrite nodules formed through a progressive increase in the porewater concentration of Ca2+ and SO42– in a vadose environment, occasionally under the influence of pedogenic processes. Partial replacement of the anhydrite by megaquartz occurred under more dilute conditions in the same type of setting, as indicated by the presence of organic filaments on the quartz crystal surfaces. In type A nodules, the dissolution of the innermost anhydrite was complete, and different types of quartz cement filled the porosity. Fracturing and meteoric cementation by calcite and minor amounts of kaolinite were the latest processes affecting these nodules. In type B nodules, the dissolution of the anhydrite was incomplete, inhibiting quartz cementation and enabling later dolomitization of the anhydrite. Dolomitization appears to have been driven by sulphate reduction, as indicated by the presence of bacterial bodies within the dolomite crystals. Dedolomitization and precipitation of barite, kaolinite and calcite spar cements occurred later under the influence of meteoric solutions. The nodules may mark the former locations of the water table and provide evidence for an episode of highly evaporitic conditions throughout wide areas of the basin. Their occurrence reveals not only a complex diagenetic history but is also indicative of palaeogeographic and palaeoclimatic conditions.  相似文献   

14.
Manganese minerals in the polymetallic nodules from the Central Pacific Ocean were studied using electron microscopy. The principal Mn minerals, being vernadite and todorokite, exhibit different electron diffraction patterns and morphological features. According to its morphological feature, todorokite shows three phases: fibrous, lamellar and lath-shaped. Both vernadite and todorokite are authigenic minerals. While vernadite was mainly precipitated directly from the relevant solution by microbiological oxidation, todorokite was separated from the solution chemically without the help of microbe. Hence, these two minerals show a close genetic relation.  相似文献   

15.
利用“海洋四号”调查船HY4—871,881航次在东太平洋海盆取得的底层水、沉积物、间隙水及多金属结核样品,研究探讨了海底水—沉积物界面系统不同物质相中结核主要成矿元素间的关系,并以此为基础讨论了结核成矿元素的来源及其成矿机制。研究表明,Mn、Fc在底层水和沉积物中表现出一定的正相关关系。而在间隙水和结核中则发生了完全相反的变化。间隙水中Mn、Fc密切共生,而结核中Mn、Fc则高度离散,这表明在沉积物早期成岩阶段,Mr~Fc在间隙水中有着相同的溶出富集机制,而在结核形成过程中则有着完全不同的沉淀聚集机制。此外,Co、Ni、Cu与Mn、Fc之间组合关系的变化则反映了不同海底作用的影响。底层水与结核及间隙水与结核相应元素之间关系的变化表明结核主要成矿元素的来源不同,Mn、Ni、Cu主要来源于间隙水,Fc、Co则主要来源于底层水。  相似文献   

16.
多金属结核中二氧化锰的测定   总被引:1,自引:0,他引:1  
夏月莲  毛海燕 《岩矿测试》1997,16(3):177-179
用过量的含有H2SO4的(NH4)2Fe(SO4)2溶液分解多金属结核的同时,还原了试样中的MnO2,然后以K2Cr2O7标准溶液滴定测定了多金属结核中的MnO2。就样品分解过程中的加热温度和时间对测定结果的影响及标准溶液的标定等问题进行了讨论,经多次测定,方法重现性好。应用此方法为新研制的多金属结核标准物质提供了MnO2的定值数据,其结果与初定值相符,无剔除值,精密度(RSD,n=8)小于06%。  相似文献   

17.
通过在中印度洋海盆结核区外的印度洋其他海域内收集到的298处多金属结核站位的分布、成分和赋存环境等地质特征,圈定了5处资源潜力区.文章对这些区域内海洋长周期沉积速率、底层水含氧量、底质类型、夏季海面平均生物生产力、底栖宏生物量密度、海底地形地貌特征和海底表层沉积物有机碳含量等数据信息进行加权评估,揭示各区域结核分布密度的高低状况,辅以结核主要有用组分含量的分类,确定了印度洋内各结核区资源潜力的划分标准.笔者认为加斯科因平原结核区为印度洋多金属结核高资源潜力区,马达加斯加海盆结核区和南澳大利亚海盆西部结核区为中等资源潜力区,克洛泽海盆结核区和南澳大利亚海盆东部结核区为低资源潜力区.未来在这些区域内,尤其是加斯科因平原结核区中有希望通过进一步调查研究,精确锁定具有更高资源潜力的次级面积结核勘探区,检验和完善资源潜力评估方法,精细量化揭示这些区域的资源潜力.  相似文献   

18.
四川龙舟山玄武岩的岩石学特征及成因探讨   总被引:5,自引:0,他引:5  
龙舟山玄武岩一直被认为是与P_2峨眉山玄武岩相当的溢流玄武岩。笔者的观察和研究表明:只有龙舟山玄武岩的上部才相当于P_2峨眉山玄武岩;下部则具有分期复杂的特点。本区玄武岩的演化具典型的板内裂谷玄武岩演化特点,玄武岩的演化同攀西裂谷的构造演化是一致的。  相似文献   

19.
Ferromanganese nodules (pisolites) form accumulations in basal layers of Pliocene-Quaternary clayey sections of Far East Russia and Vietnam. They are composed of minerals that are in common for both these regions (authigenic vernadite, feroxyhyte, goethite, halloysite, and terrigenous quartz) and minerals that are characteristic of either the northern (authigenic hollandite, lithiophorite, and bernessite) or southern (authigenic alumophorite, lepidocrocite, ferrihydrite, gibbsite, and terrigenous ilmenite) regions. Pisolites are considered to be microbial colonies with Mn and Fe oxides frequently forming biomorphs. The growth of the colonies was accompanied by dying off and mineralization of microorganisms successively from the central toward the peripheral parts of the nodules. The formation of metalliferous pisolites was linked to the oxidizing geochemical barrier developed at the interface between compact sedimentary clays and the underlying porous readily permeable weathered products of basalts.  相似文献   

20.
太平洋中部多金属结核中锰矿物的电镜研究   总被引:2,自引:2,他引:2  
萧绪琦  郭世勤 《地质学报》1992,66(3):219-226
利用电子显微术,研究太平洋中部多金属结核中的锰矿物。主要锰矿物为水羟锰矿和钡镁锰矿,它们显示不同的电子衍射花样特征和形貌特征。钡镁锰矿根据形态特征分为三个相:纤维状、片状和板条状。水羟锰矿和钡镁锰矿都是自生矿物,水羟锰矿主要是通过微生物氧化直接从溶液中沉淀生成。而钡镁锰矿则是在没有微生物参加下由溶液中分离出来的。两种矿物之间有着密切的生长关系。  相似文献   

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