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131.
滇中昆阳群火成碳酸岩的发现及其意义 总被引:3,自引:0,他引:3
在武定西矿带发现的已大理岩化的滇中昆阳群(Pt2k)火成碳酸岩富含钠长石、更长石、金云母、黑云母等硅酸盐矿物,发育火成结构构造,如斑状结构、隐晶结构,流纹构造、带状构造、气孔、杏仁构造等,与沉积围岩相比,岩石高Si、Al、Fe、Mg、Mn、P,富K2O Na2O,低钙,轻稀土富集,富含Nb、Zr、Hr、U、Th、Sr、Ba、稀土等不相容元素,与粗面质、粗安质等碱性硅酸盐岩共生。(铁)白云石(>50%)内,含有粗面南、碳酸质熔融包裹体;流体包裹体均一温度可达450℃以上。其发现证明滇中元古代曾有碳酸质岩浆活动。 相似文献
132.
地幔交代作用研究综述 总被引:1,自引:0,他引:1
地幔交代现象广泛发现于各地的碱性玄武岩或金伯利岩中的地幔橄榄岩包体中。地幔交代作用以地幔岩包体中不相容元素的高度富集和(或(出现角闪石、金云母为标志。岩石学、地球化学、同位素资料等显示地幔交代作用与岩板俯冲及部分熔融作用之间存在密切联系,地幔组成、结构、演化与大陆构造演化之间存在紧密的关系。同位素模式年龄暗示地幔交代作用可能是大陆构造活动的深部原因。 相似文献
133.
从超孔隙流体压力、粘土膜、有利的岩石组构、烃类侵位等方面介绍了深部高孔渗储集岩发育的有利条件;综述了深部储层研究方法和分析技术。目前主要从经验预测和化学反应模型两个方面来确定深部砂体的储集性能,相应的分析测试手段包括成岩场、流体动力学、生烃史、精细埋藏史、图像分析等方面的内容;提出了深部储层的分析流程。 相似文献
134.
储层质量模糊评判权重的确定方法 总被引:1,自引:0,他引:1
将模糊综合评判方法与神经网络技术相结合,利用神经网络的自学习功能来获取模糊综合评判中评价参数的权重,并通过实际储层质量评价验证了这种方法的有效性。 相似文献
135.
is paper is concerned with the geochemical features of major elements,transition metal elements,large ion lithophile elements,rare-earth elements and Sr isotopes in alkaline-ul-trabasic rocks in the Jijie complex of Lufeng,Yunnan Province,which is located in southern Sichuan-Yunnan rift zone,one of Luoci alkaline-ultrabasic complexes in central Ynnnan,Moreover,its origin pertaining primary magma,magma soure region,fractional crystallization,etc.are also discussed in the present paper. 相似文献
136.
A Study on Organic Inclusions in Clastic Reservoir Rocks and Their Application to the Assessment of Oil and Gas Accumulations 总被引:5,自引:0,他引:5
Terrigenous clastic reservoir rocks are widespread in China,and nearly all the industrial oil and gas accumulations in eastern China occur in the clastic rocks.The study shows that organic inclusions are mostly distributed in the secondary fissures and pores which were ormed in the process of oil-rock interaction,rather than in the cements or secondary enlargements. The organic inclusions are dominantly organic gas-rich or are composed of pure hydrocarbons.Homogenization temperatures range mainly from 120℃ to 130℃,which shows a relatively high maturity of organic matter.Vertical and horizontal temperature changes provide the grounds for the investigation of basin evolution and thermal fluid-kinetics-model.Fluorescence spectral characteristics o the organic inclusions indicate that oils and gases in the area studied probably have experienced two-stage or two-time migration.Micro-fluorescence rescearch is one of the effective approaches to oil/source correlation and oil migration-stage determination.The abundance and occurrence of organic inclusions is one of the indicators of oil and gas abundance and accumulation in rock layers.With the help of other informatio,organic inclusions can provide the basis for the prospective assessment of oil and gas in clastic reservoir rocks. 相似文献
137.
云南腾冲热泉金的有机地球化学研究——Ⅰ生物标志物浅析 总被引:1,自引:1,他引:1
本文主要通过对比分析研究热泉软泥中的金含量与有机质及含硫化合物的相关性。并测定泉水及软泥中含金量和软泥中有机碳含量,以及对抽提物中的饱和烃和芳烃族组分进行色谱—质谱分析,最后得出的结论:有机质的沉积环境为还原—强还原,有机质属于腐泥-腐殖型,接近和达到了成熟阶段。软泥中金含量与有机质的性质无明显相关关系,与有机碳含量也无明显相关关系,而与其成熟度相关密切。样品分析证实软泥中含硫化合物与金含量呈正相关性。对比分析了水及软泥中金含量,认为两者之间也无明显相关关系 相似文献
138.
The major gold deposits in east China are characterized by their occurrence in pre-Cambrian host metamorphic rocks,restriction in some specific stratigraphic-structural terranes,tendentious localization in ductile or ductile-brittle shear zones,association with the syntexis type granitoids,and significant remobilization,superimposition and enrichment by the later stage Mesozoic tectono-magmatic activities. 相似文献
139.
The authors have proposed a dynamic model in this paper based on the ages,rock series and associations,Sr-Nd isotopic signatures of the Mesozoic intracontinental magmatism overlying the Cathaysian and Yangtze blocks.The model describes the relation of intracontinental collision and subduction in the Tethyan tectonic regie with Paleo-Pacific oceanic plate sudbuction-strike slip-extension in the Pacific tectonic regime.During 220-150Ma,the horizontal collision between the North China block and the Yangtze block,as well as the intracontinental subduction of some divergent microcontinental terranes in the southwestern part of South China are ascribed to the influence of the Tethyan tectonic regime,giving rise to a volume of high-Isr and low-εNd(t) S-type granites only in the Cathaysian Block.During 145-90Ma,under the geodynamic backgound of subduction-strike slip-extension of the Paleo-Pacific oceanic plate on the basis of the deep tectonic process in the Tethyan tectonic regime,high-K,alkalirich calc-alkaline and shoshonitic volcano-plutonic complexes were generated in the Yangtze block,and high-K calc-alkalic and bimodal volcano-plutonic complexes were generated in the Cathaysian block.The occurrence of A-type peralkaline granites in the coastal areas of South east China indicates the end of Mesozoic intracontinental magmatism. 相似文献
140.
The garnet(Grt)and biotite(Bt) from gneisses of the Ji‘an Group are characterized by diffusion zoning at the rim,but equilibrium composition of metamorphic peak is usually remained in extensive interior area.Garnet with growth zoning is also found in the kyanite zone.In the light of microarea compositional variation of Grt and Bt,the temperature and pressure at the progressive,peak and post-peak metamorphic stages are determined by correctly using Grt Bt thermometer and GASP barometer.On this basis,a counterclockwise P-T-t path can be constructed,which reflects the closing process of an ensialic rift belt in this region during the Early Proterozoic. 相似文献