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981.
Research on preservation and enrichment mechanisms of organic matter in muddy sediment and mudstone 总被引:4,自引:0,他引:4
CAI JinGong BAO YuJin YANG ShouYe WANG XingXin FAN DaiDu XU JinLi & WANG AiPing State Key Laboratory of Marine Geology Tongji University Shanghai China Institute of Earth Sciences Shengli Oil Company Dongying China 《中国科学D辑(英文版)》2007,50(5):765-775
Using multidiscipline methodologies, the differences in preservation and enrichment mechanisms of organic matter (OM) in muddy sediment and mudstone are investigated. In clay fractions, concentra- tions of TOC and chloroform bitumen “A” are significantly higher than those in coarser fractions. This indicates that clay minerals (CM) play an important role in enriching OM. The content of chloroform bitumen “A” increases obviously in the clay fraction, which reveals that dissolvable OM is the main composition of coalesce with clay minerals. Furthermore, TG and DTA data show that OM enrichment mechanisms and preservation forms have multiplicity. Several exothermic peaks in the DTA curves demonstrate that muddy sediment and mudstone contain a number of bioclasts and amorphous OM besides dissolvable OM. Through analyzing with XRD and DTA after mudstone samples were pretreated, the conclusions can be arrived at. Firstly, CM interlayer space of XRD curves and exothermic peaks of DTA curves both change as temperature increases. Secondly, the changes of CM interlayer space and exothermic peaks are concordant and stable around 350℃. All these are the features that OM enters CM interlayers to form stable organo-clay complexes. Therefore, the combination format of OM with CM is not only surface adsorption, partial OM enters CM interlayers to form stable organo-clay complexes. Finally, through the research on OM preservation forms and enrichment mechanisms in muddy sedi- ment and mudstone, the hydrocarbon-generation processes and the global carbon cycle and budget can be explained. 相似文献
982.
983.
984.
985.
简要介绍了手持电脑和Windows CE操作系统的特点。以CMC SuperStar GPS OEM板为例,讨论了在二进制和NMEA-0183两种格式下对GPS OEM板设置时的指令格式,详细介绍了利用Windows API函数对手持电脑的串口进行操作的方法,实现了在Windows CE环境下对GPS OEM板进行设置和导航定位数据及时间信息的提取与处理等功能。 相似文献
986.
中国是世界上铝的最主要生产国和消费国,但资源储量和人均占有铝资源量严重不足。中国铝土矿具有成矿时代单一、空间分布广泛但局部相对集中的特点,成因类型以喀斯特型为主,区别于国际上以红土型为主的特点。文章在前人大量研究的基础上,对山西断隆、华北陆块南缘、黔中北-渝南和桂西南-滇东南4个最主要铝土矿成矿带的成矿规律进行了总结。并在成矿规律总结基础上,提出了当前铝土矿研究面临的关键科学问题:①地层层序与成矿物质的来源与组成问题;②深时古气候背景下重大地质事件与铝土矿成矿耦合关系问题;③铝土矿共生/伴生矿产资源的开发利用以及成矿过程问题。同时,文章还对解决上述科学问题可能采用的技术方法和研究手段予以展望。 相似文献
987.
围绕加强国内稀土资源勘探和增储上产的迫切需求,笔者在综合研究前期地质资料的基础上,对攀西牦牛坪外围龙家沟开展了以稀土找矿为主的多学科交叉综合调查评价工作。经钻探验证,龙家沟ZK001孔深部发育厚大高品位稀土矿体,科研指导找矿取得突破性进展。161件岩芯样品电感耦合等离子体发射光谱分析结果表明:钻孔ZK001总稀土氧化物(TREO)平均含量达4.87%,见矿视厚度125.76 m,核心部位高品位矿段超过60%。牦牛坪外围龙家沟厚大隐伏稀土矿体的发现与钻探验证,扩大了牦牛坪稀土矿外围的成矿前景,是科技创新指导找矿突破的又一典型实践。随着冕宁-德昌稀土成矿带成矿机制、精准勘查理论技术难题的突破、交叉学科以及模拟技术的应用,将进一步带动该区稀土找矿工作。今后,有必要持续开展牦牛坪外围稀土矿产综合地质调查工作,大幅提升中国第二大稀土资源基地的资源保障能力,对确保中国稀土资源的绝对优势地位具有重要现实意义。 相似文献
988.
989.
The environmental risk posed by small dumps of complex arsenic,antimony, nickel and cobalt sulphides
Mine waste dumps sited in the vicinity of mine workings typically consist of fragmented rock masses which in chemical terms may be defined as "complex systems", due to uncertainties in accurately simulating their behaviour, when water or aqueous solutions percolate through them. Remediation of the contamination problems created by abandoned mine dumps concerns many former mining areas from Europe to Africa. These dumps usually range in size from a few hundred thousand up to million cubic meters of rock defined as “waste” but which still contain significant amounts of potentially toxic elements. Although relatively small, they are often densely distributed in the territory impacting on surface and ground-water. This scenario is particularly applicable to the region of Sardinia, Italy, where several small dumps of uncommon sulphide minerals still exist on derelict mine sites. This paper reports on the results of a research project aimed at defining appropriate remedial measures of acid rock drainage. A dump of a Co–Ni–As–Sb complex sulphides mine was investigated and simulated in a laboratory leaching column. The column was irrigated with distilled water and a repetitive behaviour of the polluting elements concentrations in the effluents was observed for each run. Regardless of the campaign duration and the extent of the intervals between tests metal ions concentration peaks (250–50 ppm for Ni, 35–20 ppm for Co, 1.6–0.4 ppm for As, 20–15 ppm for Zn and 0.03–0.002 ppm for Sb) and acidic conditions (pH 2.5–3.5), on resumption of each irrigation, was noticed. As percolation continued, the ion concentrations decreased within the discharge limits after the replacement of only two pore volumes of the column material. This produces the conception that a sufficiently long rainfall period could remediate the polluting effects. Conception contradicted by field experiences: sporadic rainfall events, typical of the region, are not sufficient to completely leach out the metal ions. The repetitive nature of the leaching processes, both quantitatively and qualitatively, can be explained only by the activity of a microflora thriving in the rock mass even during long dry periods. Microbial tests and neutralisation campaigns confirmed this hypothesis and suggested that any effective remediation strategy must take into consideration the interaction between environmental factors with microbiological activities. 相似文献
990.
粤北棉花坑(302)铀矿床围岩蚀变分带的铀矿物研究 总被引:4,自引:4,他引:0
粤北棉花坑(302)铀矿床是华南最大的花岗岩型铀矿床。本文以该铀矿床的一个代表性钻孔岩心为研究对象,利用电子探针对该钻孔中的铀矿物进行系统研究。该钻孔岩心具有明显的垂直围岩蚀变分带现象:从上到下可分为四个带,分别为:正常花岗岩或弱蚀变带(Ⅰ带);高岭石化、绢云母化带(Ⅱ带);强绢云母化、绿泥石化带(Ⅲ带);矿化带(Ⅳ带)。铀矿物类型也具有分带现象:Ⅰ带、Ⅱ带、Ⅲ带的铀矿物主要是晶质铀矿和铀钍石;矿化带Ⅳ带的铀矿物主要有沥青铀矿、铀石、钛铀矿、铀钍石四种类型。运用电子探针测年方法对不同蚀变带的晶质铀矿和沥青铀矿进行定年,获得晶质铀矿的化学年龄为165±3.1Ma,代表长江岩体的形成年龄;沥青铀矿的化学年龄可分为四组:~120Ma、~102Ma、~92Ma和~68Ma,代表矿区多期次的热液活动时间,也可代表粤北地区多期次铀成矿作用年龄,前三组可能代表早期铀成矿事件,第四组为主成矿期。广泛发育的热液蚀变促使U发生活化、转移,进而在有利空间富集成矿。对典型铀矿床作深入细致的蚀变分带研究工作,有助于提高对成岩成矿过程的认识。 相似文献