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91.
应用三维地震资料设计水平井的轨迹,用人工合成记录标定层位和岩性并进行精细的构造解释和储层横向预测,对测区速度场进行研究,利用Geoquest 人机联作解释系统编绘层拉平图、转弯测线剖面图,不整合面构造图,各套油层顶面构造图,沿地层倾向设计水平井的轨迹.经两口井钻探,钻遇不整合面的误差0.19%—0.39%,一口井平均钻遇油层204m,相当9口直井的效益.用地震资料设计巷道水平井的关键是油层标定、深度标定和确定油层走向,用人机联作系统绘制水平切片图、反射波振幅图、油层顶构造图,设计了在油层内钻探的巷道井.经钻探,钻遇不整合面的误差0.07%,在真厚度8.23m 的油层内钻进563m.  相似文献   
92.
The Main Zone of the Hidaka Metamorphic Belt is an uplifted crustal section of island-arc type. The crust was formed during early Tertiary time, as a result of collision between two arc–trench systems of Cretaceous age. The crustal metamorphic sequence is divided into four metamorphic zones (I–IV), in which zone IV is in the granulite facies. A detailed study of the evolution of the Hidaka Belt, based on a revised P–T–t analysis of the metamorphic rocks, notably a newly found staurolite-bearing granulite, confirms a prograde isobaric heating path, after a supposed event of tectonic thickening of accretionary sedimentary and oceanic crustal rocks. During the peak metamorphic event (c. 53 Ma), the regional geothermal gradient attained 33–40° C km?1, and the highest P–T condition obtained from the lowest part of the granulite unit is 830° C, 7 kbar. In this part, XH2O of Gt–Opx–Cd gneiss is about 0.15 and that of Gt–Cd–Bt gneiss is 0.4. The P–T–XH2O condition of the granulite unit is well within a field where fluid-present partial melting of pelitic and greywacke metamorphic rocks takes place. This is in harmony with the restitic nature of the Gt–Opx–Cd gneiss in the lowest part of the granulite unit. The possibility that partial melting took place in the Main Zone is significant for the genesis of the peraluminous (S-type) granitic rocks within it. The S-type granitic rocks in this zone are Opx–Gt–Bt tonalite in the granulite zone, Gt–Cd–Bt tonalite in the amphibolite zone, and Cd–Bt–Mus tonalite in the Bt–Mus gneiss zone. The mineralogical and chemical nature of these strongly peraluminous tonalitic rocks permit them to be regarded as having been derived from S-type granitic magma generated by crustal anatexis of pelitic metamorphic rocks in deeper crust.  相似文献   
93.
吴联源  傅国民 《岩矿测试》1991,10(4):274-278
本文研究了一种多功能雾化室装置,以探索ICP-AES技术中溶液进样的新方式;并对雾化系统的主要参数进行测试,取得最佳的匹配条件。该雾化室装置包括旋流雾化、循环雾化和氢化-雾化等系统,可在同一操作条件下进行工作,适应多种分析的需要。并可任意选择合适的雾化射程来增强元素谱线强度的信背比和雾化的稳定性,以达到改善分析的精密度和检出限。  相似文献   
94.
地球内部非弹性介质广泛存在,垂向线性连续变化非弹性介质模型具有重要理论与实际意义,本文利用复速度概念推导得到了复速度随深度线性连续变化的非弹性介质中地震波射线轨迹与等时线方程.理论结果表明:在线性连续变化非弹性介质中,射线轨迹呈圆形,等时面的形状为椭圆.最后对射线轨迹与等时线方程的适用性条件进行了讨论.  相似文献   
95.
The Palghat Gap region is located near the centre of the large southern Indian granulite terrane. at the northern edge of the Kodaikanal charnockite massif. The dominant rock types in the region are hornblende-biotite ± orthopyroxene gneisses and charnockites along with minor amounts of intercalated mafic granulite, metapelite and calc-silicate. The P-T estimates from garnetiferous mafic granulites and metapelite samples are generally in the range 9-10 kbar and 800-900 C using both conventional thermobarometric methods and the TWEEQU thermobarometry program. These P-T estimates, which should be taken as minimum values, are among the highest yet reported for South Indian and Sri Lankan granulites. The occurrence of orthopyroxene + plagioclase symplectites around embayed garnet grains in the mafic granulites and cordierite rims around garnet grains in metapelite suggest an isothermal decompression-type path. Similarly, a core-rim P-T trajectory indicates c. 3 and 7 kbar decompression at high temperature in the mafic granulites and metapelite, respectively. In both rock types, the key to the determination of the retrograde P-T path was the recognition of small amounts of second generation plagioclase with a more anorthitic composition than the matrix plagioclase. The preservation of high garnet-pyroxene temperatures in the mafic granulites (despite small garnet grain size) suggests rapid cooling of the terrane. Calculated minimum cooling rates range from 8 to 80 C Ma-1. Such cooling rates are more rapid than those associated with normal isostatic processes and suggest that the terrane was tectonically exhumed at high temperature.  相似文献   
96.
The prograde amphibole that coexists with chlorite, epidote, muscovite, albite, quartz and hematite in Sanbagawa schists was examined to investigate the relationship between the prograde P-T paths of individual rocks and the metamorphic field gradient in the Sanbagawa metamorphic belt, central Shikoku. The amphibole changes from actinolite, through ferri-winchite and crossite, to barroisite and hornblende with increasing grade along the metamorphic field gradient. However, the sequence of prograde amphibole compositions in each sample varies in different mineral zones. The general scheme can be summarized as: magnesioriebeckite-riebeckite crossite in the upper chlorite zone of lower-grade rocks; crossite or glaucophane barroisite in the garnet zone of medium-grade rocks; and actinolite or winchite barroisite hornblende in the albite-biotite zone of higher-grade rocks. Changes of amphibole composition indicate that the prograde P-T path recorded in the higher-grade rocks was situated on the higher-temperature side of that of the lower-grade rocks and on the lower-pressure side of the metamorphic field gradient. The systematic change of P-T paths implies an increasing d P /d T during continuous subduction. These features can be interpreted as documenting prograde metamorphism within a young subduction zone that has a non-steady-state geotherm.  相似文献   
97.
Using long path UV absorption spectroscopy we have measured OH concentrations close to the earth's surface. The OH values observed at two locations in Germany during 1980 through 1983 range from 0.7×106 to 3.2×106 cm-3. Simultaneously we measured the concentrations of O3, H2O, NO, NO2, CH4, CO, and the light non methane hydrocarbons. We also determined the photolysis rates of O3 and NO2. This allows calculations of OH using a zero dimensional time depdendent model. The modelled OH concentrations significantly exceed the measured values for low NO x concentrations. It is argued that additional, so far unidentified. HO x loss reactions must be responsible for that discrepancy.  相似文献   
98.
吉南古元古代集安群泥质变质岩P—T—t轨迹及其地质意义   总被引:3,自引:0,他引:3  
吉南古元古代分布区大地构造划分为辽吉裂谷系和浑江裂陷槽,集安群是辽吉裂谷系早期产物。泥质变质岩呈北东向分布于裂谷带内,经历了形成期后的中高级变质作用。本文在岩石建造、地质构造等研究基础上,通过变质作用研究,利用变质石榴石环带分析方法,建立了集安泥质变质岩P-T-t轨迹。该轨迹表明集安群形成以来经历了两次拉张变质作用。在变质作用动态过程中,泥质原岩发生变质变形,P-T-t轨迹反映了该区古元古代地质演  相似文献   
99.
微量元素在矿源岩(层)中迁移遵循严格的级序路径,并且存在两种迁移倾向。迁移的结果图象是一分维结构。两种共轭地球化学异常出现的有利环境是温度高度反差地区和大断裂系及其附近。  相似文献   
100.
钢筋混凝土建筑抗倒塌设计   总被引:14,自引:2,他引:14  
建筑抗倒塌问题近年来在欧美国家得到广泛关注,并颁布了相关的设计规范和标准。我国还没有制定有关建筑抗倒塌方面的规范和标准。本文提出一种基于建筑危险性的钢筋混凝土建筑抗倒塌设计方法。该方法将钢筋混凝土建筑分为四类,通过设置拉杆连接系统和Alternate Path设计提高建筑抗倒塌能力。  相似文献   
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