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101.
本文介绍了碱金属硼酸盐的一些基本知识,主要回顾了其中Li2O—B2O3体系的研究历史,讨论了该体系结构与性质的关系并总结了Li2O-B2O3晶态及非晶态物质作为新型功能材料的研究进展。  相似文献   
102.
北京地区遥感环形构造信息提取与金矿预测   总被引:7,自引:2,他引:7  
解译了北京地区航片上的环形构造,对环形构造解译图进行了数字化处理,运用数理统计方法分析了环形构造的空间分布特征及其与金矿化作用的关系,最后得到了环形构造密度异常与金矿分布之间具有正相关关系等新认识。  相似文献   
103.
无锡、常州郊区发生地裂缝近年来,无锡石塘湾西蔡一秦村~带、常州横林分别出现了地裂缝,其中以钱桥毛村园最为严重,该处地裂缝于1991年夏初步形成,随后不断扩大,目前已具一定规模,长约700m,总体宽约60m,呈近东西向分布,并造成附近数十间楼房产生大量...  相似文献   
104.
A core from the Cambay Shale Formation of the Cambay Basin, containing immature Type III organic matter, was pyrolysed at 300°C for different durations of time to different maturation levels. Fractionation effects were studied employing a three-step extraction technique after removal of the expelled pyrolysate. The extractable organic matter (EOM) obtained on extraction of the whole core is assumed to be that present in open pores, while that obtained on finely crushing the sample is assumed to be that present in closed pores. The EOM obtained from 1 cm chips is termed EOM from semi-open pores. The gross composition of the pyrolysates expelled during pyrolysis is not similar to the oils reservoired in the area, and there is no significant fractionation observed between expelled pyrolysates and unexpelled EOM. Our study indicates movement of fluids between closed, semi-open and open pores. In both systems, there is a higher concentration of EOM in open pores than in semi-open and closed pores, and the fraction of EOM in open pores is much greater in the artificial system than in the natural system. Fractionation effects on n-alkane and isoprenoid hydrocarbon-based parameters were also studied. n-Alkenes are present in semi-open and closed pores of the immature core and in the core after it was pyrolysed to 300°C for 6 and 48 h, but are absent in the open pores. n-Alkenes are present in closed pores in the naturally matured core. Presence of n-alkenes in the pyrolysates expelled during the 6 and 48 h experiments, but their absence in the open pores of the core, indicates that expulsion also occurs through temporary microfractures during laboratory pyrolysis, whereas in the natural system expulsion from closed pores seems to be only via semi-open and open pores.  相似文献   
105.
Organic matter was experimentally extracted by supercritical fluids(CO2 1% isopropanol)from petroleum source rocks of different thermo-maturities at different buried depths in the same stratigraphic unit in the Dongying Basin.The results show that supercritical fluid extraction(SFE)is more effective than Soxhlet extraction(SE),with higher amounts and greater varieties of hydrocarbons and soluble organic matter becoming extractive.The supercritical CO2 extraction is therefore considered more valuable in evaluation of petroleum source rocks and oil resources,particularly those of immature types.  相似文献   
106.
本文研究了以cHCl=8mol·L-1盐酸为移动相,以聚四氟乙烯负载的钽试剂-CHCl3为固定相反相萃取层析钛(Ⅳ)的新体系,柱上层析的钛用cHCl=3mol·L-1盐酸洗脱后经二安替比林甲烷光度法测定,不仅钛回收率可达100%,并可使钛(Ⅳ)与多种离子分离。能用于矿物岩石类复杂样品及其他物质中钛的分离富集与测定,方法简便快速。  相似文献   
107.
新疆阿尔曼太蛇绿岩时代的Nd—Sr同位素地质研究   总被引:15,自引:7,他引:15  
黄萱  金成伟 《岩石学报》1997,13(1):85-91
本文通过测定采自新疆阿尔曼太兔子泉一带蛇绿岩的堆晶辉长岩、辉绿岩和安山玢岩,获得Sm-Nd等时年龄为561±41Ma,εNd(t)=6.1,Rb-Sr等时年龄为392±17Ma,(87Sr/86Sr)i=0.7041,前者为蛇绿岩的形成时代,后者为蛇绿岩遭受后期变质作用的时间。札河坝-阿尔曼太蛇绿岩的形成环境可能是古亚洲洋向南俯冲引起的弧后盆地  相似文献   
108.
The Turpan-Harmi (abbreviated to Tuha below) Basin is a typical basin of coal-generated oil accumulation in China. The Middle-Lower Jurassic coal measures are considered the main source beds. Hence, both desmocollinite and suberinite are considered the contributors for coal-generated oil. Principal geochemical features of the crude oil in the Tuha Basin are rich in alkanes (70%—80%), high pristane/phytane ratio (6—8), abundant heavy carbon isotope (δ13C PDB= -26%–-23%) and absolute GP sterane predominance. The hydrocarbon generation process from the coal series is characterized by multistages, early generation and early expulsion.  相似文献   
109.
Organism relics or kerogens in oils are first obsenred by a confocal laser scanning microscope (CLSM) and a transmission electron microscope (TEM). The complexes of kerogens in oils are characterized by the presence of a great variety of microfossils or macerals. These kerogens in oils are mainly the residues of the original organic substances from which oil formed, and minor kerogens from enclosing rocks enter the oils, therefore, the components and types of the kerogens in crude oils can serve as an indirect indicator of oil-source rock correlation. This method was applied to Jurassic oils in the Junggar Basin and the Turpan-Hami Basin, and there are two types of the kerogens in oils: one containing a lot of macerals from terrestrial plants may derive from coals, and the other, characterized by a high content of microscopic algae, fungus spores and Acritarch, may originate from Permian organic matter. In addition, the reflectance of the vitrodetrinites in oils can be used as an indicator of oil-source rock correlation.  相似文献   
110.
中国侏罗系煤成油若干问题   总被引:7,自引:0,他引:7  
胡社荣  方家虎 《地质论评》1997,43(2):155-161
在阐述了煤成油的概念,总结和评述了煤生油显微组分,生油门限,生油范围和生油高峰等问题后,本文通过吐哈等盆地侏罗系煤生油显微组分组成特征,可溶有机质演化,成熟度和有机质丰度,油源及原油成熟度对比;含煤岩系中煤层和泥岩的厚度及总量和煤及泥岩最高沥青和总烃转化率的对比; 其族组成和煤成原油的族组成特征的对比,提出了中国侏罗系煤成油盆地中泥岩比煤层对煤成油田形成有大的贡献看法。  相似文献   
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