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81.
本文从超高压变质作用的矿物学、P-T-t轨迹和超高压地体抬升、保存机制三个方面总结了近年来超高压变质作用研究所取得的重要进展和存在的问题。超高压变质作用的矿物学研究正在向深入发展,其P-T-t轨迹具有三种成因类型。而其超高压地体的抬升、保存机制则是争论的焦点,其中增生楔模式(Platt,1987)和连续俯冲─仰冲机制较好地解释了抬升过程,但也存在一些问题需进一步研究。 相似文献
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本文讨论了GPS工程控制网的最优化设计问题;通过对GPS工程控制网的精度和可靠性分析,建立了应用点位精度矩阵相关性优化GPS网的数学模型;针对解算中存在的问题,提出了最短路径法寻找整数变量线性规划问题的最优解。 相似文献
84.
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
85.
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
86.
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
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88.
苏鲁交界及南黄海地区地震波速比的变化特征 总被引:2,自引:0,他引:2
本文主要应用多台波速比和单台波速比的方法,计算了苏鲁交界及南黄海(北纬35°35′至36°00′,东经117°00′至121°00′)范围内,1984到1991年7月发生在该区域的163次ML≥1.7地震的波速比值,并对波速比结果进行t检验和模糊数学分析识别。分析结果发现,1985年1月至11月出现了不连续的波速比低值异常时段,模糊数学识别的异常从属函数在这段时间也呈现高值。异常恢复后,1987年 相似文献
89.
This paper deals with the influence of different humic substances (HS) on the enzyme activity (EA) of the proteolytic enzyme pronase E. The EA was determined by analyzing the concentration of the amino acid valine hydrolyzed from caseine. For amino acid analysis, a flourescence detector was used after precolumn derivatization and HPLC-separation of the hydrolysis products. The data show that the presence of HS has no adverse effects on amino acid analysis. Based on this result, a decrease of EA was observed in the presence of HS acting as enzyme inhibitors. Clear inhibition effects could be seen for different fulvic acids (HO3 FA, FBR FA and FBR 1.0 FA) at concentrations of 150 mg/L. In case of FBI-2 FA, higher concentrations were necessary to decrease the EA significantly. At an inhibitor concentration of 1500 mg/L the EA was mostly found to be less than 50%. The standard deviations of the results don't allow a differentiation between the HS of different origin and treatment. Specifying HS according to their influence on EA has to remain uncertain. As shown in a kinetic study of the hydrolysis of L-Leucine-2-naphthylamide-hydrochloride, the inhibitor HO3 FA decreases the maximum velocity of the reaction but has no effect on the Michaelis constant. These results indicate that this HS acts as a noncompetitive inhibitor. 相似文献
90.
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