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61.
全极化探地雷达地下管道分类识别技术 总被引:1,自引:0,他引:1
常规探地雷达大多数是单极化雷达,单极化雷达只能获得单极化数据,对复杂环境中管道准确快速地识别比较困难。为了解决此问题,本文采用了全极化探地雷达识别管道的方法,提取了单一管道目标、多个管道目标中任何一个管道目标和受其他目标影响的管道目标的极化属性。结果表明,全极化探地雷达技术对处于极化属性受到影响环境下的管道目标均能较好地识别。因此,全极化探地雷达能够获得更加全面的目标体极化信息,有效地解决了复杂环境中管道准确快速识别比较困难的问题。 相似文献
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The Late Cretaceous ükapili Granitoid including mafic microgranular enclaves intruded into metapelitic and metabasic rocks, and overlain unconformably by Neogene ignimbrites in the Ni de area of Turkey. It is mostly granite and minor granodiorite in composition, whereas its enclaves are dominantly gabbro with a few diorites in composition. The ükapili Granitoid is composed mainly of quartz, K-feldspar, plagioclase, biotite, muscovite and minor amphibole while its enclaves contain mostly plagioclase, amphibole, minor pyroxene and biotite. The ükapili Granitoid has calcalkaline and peraluminous (A/CNK= 1.0-1.3) geochemical characteristics. It is characterized by high LILE/HFSE and LREE/HREE ratios ((La/Lu) N = 3-33), and has negative Ba, Ta, Nb and Eu anomalies, resembling those of collision granitoids. The ükapili Granitoid has relatively high 87Sr/86Sr (i) ratios (0.711189-0.716061) and low εNd (t) values (-5.13 to -7.13), confirming crustal melting. In contrast, the enclaves are tholeiitic and metaluminous, and slightly enriched in LILEs (K, Rb) and Th, and have negative Ta, Nb and Ti anomalies; propose that they were derived from a subduction-modified mantle source. Based on mineral and whole rock chemistry data, the ükapili granitoid is H-(hybrid) type, post-collision granitoid developed by mixing/mingling processes between crustal melts and mantle-derived mafic magmas. 相似文献
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在偏光显微镜的锥光系统中,垂直二轴品光率体─—圆切面与光轴面交线的切面干涉图此处定义为临界干涉图。结合球面和平面解析法可以证明,这种干涉图消光影一般为双曲线形,但具体形状与晶体2V角及从0°位置(光轴面平行上或下偏光镜振动方向)旋转的角度有关。它与已知其它切面干涉图的最大区别是,当晶体从0°位置旋转45°时,消光影为一条与目镜横丝或纵丝夹45°角的直线,它到视域中心的距离随晶体2V角的减小而加大,因而在特定物镜数值孔径和晶体折射率的情况下,只有较大2V角晶体的这条消光影才会处在视域之内。在观察橄榄石和角闪石晶体临界干涉图时证实了它的上述特性。 相似文献
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Hydrothermal Fluid Evolution Associated with Gold Mineralization at the Wenyu Mine, Xiaoqinling District, China 总被引:3,自引:0,他引:3
Neng JIANG 《Resource Geology》2000,50(2):103-112
Abstract: The Wenyu mesothermal gold deposit is located in the Xiaoqinling district about 1000 km southwest of Beijing in central China. It occurs in the Late Archean to Early Proterozoic metamorphosed volcanic and sedimentary rocks. Three distinct stages of veins have been identified: (I) gold‐poor quartz–pyrite veins, (II) gold‐rich sulfide–quartz veins, and (III) gold‐poor carbonate–quartz veins. Stage II can be subdivided into IIa and IIb. Gold typically occurs as fracture‐fillings associated with chalcopyrite and galena. Fluid inclusions were examined in quartz samples from veins of both stage I and II. Three types of fluid inclusions are identified: CO2–H2O, CO2–rich, and aqueous inclusions. The first two types are of primary in origin. The last type occurs in two ways: coexisting with CO2–H2O and CO2–rich inclusions and thus primary in origin; and occurring along late healed fractures and hence secondary in origin. CO2–H2O inclusions display progressively decreasing Th and increasing Thco2, from the highest Th (311–408C) and lowest Thco2 (average 18C) in stage I quartz through middle Th (284–358C) and ThCO2(average 25C) in stage IIa quartz to the lowest Th (275–314C) and highest ThCO2 (average 28C) in stage IIb quartz, indicating an evolving H2O–CO2–NaCl fluid system. CO2–rich and primary aqueous inclusions show consistent ThCO2 or Th with their coexistent CO2–H2O inclusions. Whereas the secondary aqueous inclusions in stage I and IIa quartz have almost the same Th and salinity as the primary aqueous inclusions in stage IIb quartz. Comparing with CO2–H2O inclusions, these non–CO2, low salinity aqueous inclusions may come from different origin, most probably meteoric water. Unlike in both stage I and IIa quartz, fluid inclusions in stage IIb do not show evidence of fluid immiscibility. The fact that most of gold is associated with stage IIa and IIb veins and not with veins of stage I which is the main stage of vein formation suggests that gold deposition occurs at the later stage of fluid immiscibility. The continuing phase separation led to the deposition of large amounts of gold at the Wenyu mine. 相似文献
66.
Cs. Sajg 《Organic Geochemistry》2000,31(12)
Biological marker maturity parameters were used to estimate the minimum HC generation temperatures of crude oils from Eastern Hungary. More than 50 oils and oil shows were analysed. Molecular- and homologous-ratios of biological marker compounds (triterpanes, steranes, mono- and triaromatic steroid hydrocarbons) were used as maturation parameters. The oils have at least five maturity stages, i.e. they have been generated under different thermal conditions. The highest reservoir temperature in each group was chosen as the best estimate of the groups' temperature just below the generation temperature, i.e. reservoirs of the group might be expected to be at shallower depths (lower temperatures) than those of the generation zone due to vertical migration into pools. For each maturation level, a threshold temperature range for genesis was inferred from reservoir temperatures; they are from 130–135°C for the least mature oils to 210–215°C for the most mature oils. In the least mature oils cracking was not observed, hence carbon–carbon cracking reactions had not taken place during their genesis. The most mature oils are intensively cracked oils; they are almost condensates. Two major genetic groups (families) of oils were found in the area. Both are present in each maturation level. The effects of migration were checked, and no influence on maturation was found. A number of the oils are in overpressured reservoirs within, or just above, the zone of the present-day active oil generation, hence the present-day temperatures of the pools must have been maximum temperatures. Contrary to the traditionally accepted temperature range for petroleum generation–maturation reactions (50–150°C), there is strong evidence from this study that the onset of oil generation requires temperatures higher than 130°C and is still proceeding above 215°C. 相似文献
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69.
四川盆地东部垫江凹陷三叠系嘉陵江组岩盐氯同位素特征与成钾指标研究 总被引:1,自引:0,他引:1
垫江凹陷位于四川盆地东部,是四川盆地三叠纪时期重要的成盐凹陷之一,但当时古卤水是否达到钾盐沉积阶段,是否具备形成海相钾盐的良好条件,一直存在争议。本文通过对垫江凹陷长平3井、高探1井和ZK001井嘉陵江组岩盐样品进行化学成分分析,以及对长平3井典型岩盐样品进行氯同位素分析来判断古卤水沉积阶段和成钾条件。结果发现垫江凹陷三叠系嘉陵江组岩盐δ37 Cl值均为负值,均小于-0.32‰,最低达到-1.18‰,绝大部分岩盐样品溴氯系数大于0.31,有很大一部分样品溴氯系数超过0.45,进一步表明垫江凹陷在嘉陵江期古卤水浓缩已达到钾石盐析出阶段,与岩盐包裹体成分分析结果一致。综合气候-物源-构造因素,认为垫江凹陷三叠纪嘉陵江期气候条件炎热,物质来源丰富,存在次级凹陷,古构造条件优越,具备良好的成钾潜力。 相似文献
70.
从频谱激电法的发展概况﹑仪器系统、数学模型、反演方法及应用等方面,介绍了频谱激电法的研究现状。介绍了频谱激电法目前常用的仪器系统:SIP?FUCHSII和V8,数据模型主要有:Cole-Cole、常相位角模型CPA、普通化的Cole-Cole模型和理论模型SNP。反演方法简要介绍了几种常用算法,反演算法也由一维、二维发展到三维。列举了频谱激电法近年来在矿产资源、水资源调查等多个领域的应用概况,展望了频谱激电法的发展方向:(1)同时考虑激电效应和电磁效应的三维电磁场正演计算技术是研究的前沿和热点;(2)频谱激电法对有机污染的探查成为未来应用研究的新领域。 相似文献