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831.
The accurate observation of the microphysical structure of cloud and precipitation plays an important role in understanding the formation of clouds and precipitation. In-situ measurement using measuring instruments carried by meteorological balloons is an effective way to obtain the microphysical properties of cloud and precipitation particles, which is a supplementary means for aircraft to observe cloud and precipitation particles. This observation method plays a more and more important role in in-situ measurement. According to the difference of the working principle of the existing balloon-borne cloud and precipitation particles probes, the detectors can be divided into particle impact-sampling sensors, particle imaging sensors, light-scattering sensors, light intensity attenuation sensors and charge measurement sensors. The working principles, key technologies and main advantages and disadvantages of typical instruments were summarized, and their applications to detailed cloud structure acquisition, cloud remote sensing method establishment, cloud and precipitation physical process research and parameterization, and scientific observation of thunderstorm clouds were briefly introduced. Finally, the development trend of balloon-borne cloud precipitation particle detectors was prospected, which will provide reference for related technical research and equipment development.  相似文献   
832.
Subducted sediments play an important role in crust-mantle interaction and deep mantle processes, especially for subduction zone magmatism and mantle geochemistry. The current rate of Global Subducting Sediments (GLOSS) is 0.5~0.7 km3/a. The GLOSS are composed of terrigenous material(76 wt.%), calcium carbonate(7 wt.%), opal(10 wt.%) and mineral-bound H2O+(7 wt.%). The chemical compositions of GLOSS are similar to those of upper continental crust which is mainly controlled by the terrigenous materials, and yet the materials formed by marine processes will dilute the terrigenous materials. The components of subducted sediments are different among trenches. In the accretionary margin, the components of subducted sediments are similar to those of the upper crust, while in the non-accretionary margin the components are terrigenous materials plus those produced by marine processes. During subduction, subducted sediments will released fluids, melt or supercritical fluid to affect island arc/back-arc basin magmatism by means of aqueous fluid or sediment melt. In addition, a part of subducted sediments, together with underlying altered oceanic crust/lithosphere, recycle into the mantle and contribute to the mantle heterogeneity. Geochemical tracers indicate that subducted sediments play variable contributions to the magmatic processes in different tectonic setting. Thus, subducted sediments play an important role in two relatively independent dynamics systems (plate tectonics and mantle plume), as well as related mantle evolution models. As a result, by accurately calculating the compositions of subduction sediments and using various geochemical indicators, we can further limit the input and output fluxes of various elements or isotopes, and then obtain more accurately residual subducted components, which can provide us some important clues for geodynamic process.  相似文献   
833.
吉林省西林河金矿构造特征及找矿方向   总被引:2,自引:0,他引:2  
对矿区划分了太古宙、元古宙、中生代和新生代四个构造层;整个矿区为一棋盘格子形构造体系;主干构造形迹为由东、中、西三个韧性挤压剪切带,金矿的主要成矿构造是西部韧性挤压、剪切带,主要找矿方向为西带F6及其派生的近南北向剪切断裂群。  相似文献   
834.
着重介绍了目前变质作用P-T─t轨迹研究在变质作用温压确定、变质作用不同阶段时间标定、变质作用动态演化过程的组构标志、变质作用演化热模拟以及变质作用P─T─t轨迹与大地构造环境之间关系等方面所存在的若干问题。  相似文献   
835.
本文分析了威海市杨家滩不源地第四系冲洪积-海相沉积物分规律和水文地质特征;在此基础上,应用有限单元方法进行了地下水量评价和预测水源地地下水位的变化趋势;提出了最优开采方案。  相似文献   
836.
提出了两种新的生油岩测井评价方法,即基于砂泥岩导电机理,借助泥质砂岩导电方程:Waxman-Smith方程计算含水泥岩电阻率R0值及生油岩的电阻率孔隙度R.然后用实测Rt减去R0值,其差值反映了生油岩的有机质丰度(即重叠法);用三孔隙度测井计算的生油岩总孔隙度T,减去电阻率孔隙度R,其差值也反映了生油岩的有机质丰度(即双孔隙度法).该方法的最大优点是在现场缺少生油岩实验室分析样品时可以快速评价生油岩的有机质丰度。  相似文献   
837.
For the identification of multi-degree-of-freedom structures, it is not practical to identify all of the parameters included in the structures because enormous computation time is required and because identifiability may not be possible. In this paper, a localized identification approach through substructuring is formulated in the frequency domain. A technique of spectral smoothing is incorporated in the approach to deal with noise-corrupted data. The proposed approach can be used to identify the structural parameters in any part of interest in a structure. The numerical investigations for a lumped mass-spring-dashpot system indicate that faster convergence and higher accuracy are achieved and the noise influences on the identified results are reduced greatly by spectral smoothing. The approach also applies to whole-structure identification if the required records available and the numerical example shows that higher accuracy results are obtained with less cpu time and more poorly guessed initial values as compared with the general complete-structure identification.  相似文献   
838.
康定杂岩时代及成因探讨   总被引:21,自引:0,他引:21  
胥德恩  陈友良 《地质论评》1995,41(2):101-111
康定杂岩是康滇地轴上一套复杂岩系,由紫苏辉长质暗色杂岩、英云闪长质浅色杂岩及复成分混合杂岩构成。岩石结构构构造,铀、钍及稀土特表明,主体为岩浆杂岩,包含大量具层状痕迹的变质杂岩。大量的锆石U-Pb年龄及其它同位素年龄表明,岩浆岩属晋宁-澄江期。变质杂岩时代与河口群相当。  相似文献   
839.
陈仁义  刘玉琳 《地质论评》1995,41(2):165-173
索尔库都克矿床是近年来新疆境内探明的中型铜(钼)矿床。对其成矿地质环境、矿床地质特征、夕卡岩其分带的研究表明,该矿床之夕卡岩与Д.C.柯尔仁斯基所划分的类夕卡岩相类似。该夕卡岩是由凝灰砂岩、安山玢岩等变质形成的。流体包裹体和稳定同位素的研究表明,该矿床是我国特殊的层状夕卡岩矿床,与接触交代夕卡岩矿床明显不同。  相似文献   
840.
高边坡的岩体结构和稳定性研究是工程地质研究的一个重要课题。本次探测使用高分辨率数字地震仪和反射地震CT方法,对金川露天矿高边坡的岩体结构进行了深入细致的探测与研究,清楚地揭示了边坡岩体中优势结构面的产状和组合关系,以及边坡表层松动带厚度分布,未发现顺坡软弱岩层。  相似文献   
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