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81.
本文简要介绍泉州市地震局依靠各级政府、有关部门和全社会的共同努力 ,以落实地震应急预案为楔机促进“预、防、救”三大体系工全面发展的工作经验 :一、以落实《地震应急预案》为抓手 ,争取项目 ,以项目带动一切 ;二、结合社会转型全面加大防震减灾知识宣传力度 ;三、不以经费的来源划分你我 ,动员全社会的力量建立健全预警应急机制。 相似文献
82.
Introduction Based on the elastic theory of the hard inclusion (Dobrovolskii, 1991), we developed an inclusion theory of rheologic medium, and applied the results of bulk-strain field of a rheologic inclusion model to explain the spatial-temporal evolution process of earthquake precursors (SONG, et al, 2000). In the former paper (SONG, et al, 2003), we derived the viscoelastic displacement field of the rheologic inclusion model on the basis of the analytic expression of displacement field o… 相似文献
83.
Avigdor Rutenberg 《地震工程与结构动力学》2004,33(7):881-896
The distribution of seismic base shear demand among ductile flexural cantilever walls, comprising the lateral load resisting system of a multistorey building, is studied. It is shown that the base shear force demand depends on the sequence of hinge formation at the wall bases, and this in turn depends on the relative wall lengths. Hence, the routine elastic approach in which the shear forces are allocated per relative flexural rigidity or (when some consideration is given to plastic hinge formation) to moment capacity at the wall base, may appreciably underestimate the shear force demand on the walls, particularly the shorter (usually the more flexible) ones. A simple procedure yielding the results of ‘cyclic’ pushover analysis is proposed to predict the peak seismic wall forces for a given total base shear when plastification is confined to the wall base. The effects of plastic hinges developing at higher floors on (1) shear distribution among the walls and (2) the in‐plane floor forces are also considered. Two numerical examples are presented to demonstrate the main points made. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
84.
There are numerous hot springs with temperatures ranging from 30 to 100 °C in Biga peninsula and they occur throughout the peninsula. The result of this study shows that the region is under a tectonic compressional regime. The investigation of the faults and fractures in the region indicates that the region has been affected first by N–S and then E–W compression since the Middle Miocene. Opening fractures and antithetic and synthetic faults due to the compressional movements provide paths for the deep circulation of water. In addition, the tectonic movements, granitic intrusion and volcanic activity have also played important roles as heat sources for the geothermal systems. 相似文献
85.
针对目前地热井施工技术现状及地热井使用中常见的问题,进行了较为详细的分析和研究,并就今后发展方向和建议进行了初步探讨。 相似文献
86.
关注我国“工业测量”事业的发展 总被引:1,自引:0,他引:1
尝试给出工业测量的定义、范畴、目标的分类和多样性,简要叙述工业测量手段的多样性,列举待研制和待改进的工业测量集成系统的名称以及所依托的几何传感器的类别。 相似文献
87.
The gravity field of the earth is a natural element of the Global Geodetic Observing System (GGOS). Gravity field quantities are like spatial geodetic observations of potential very high accuracy, with measurements, currently at part-per-billion (ppb) accuracy, but gravity field quantities are also unique as they can be globally represented by harmonic functions (long-wavelength geopotential model primarily from satellite gravity field missions), or based on point sampling (airborne and in situ absolute and superconducting gravimetry). From a GGOS global perspective, one of the main challenges is to ensure the consistency of the global and regional geopotential and geoid models, and the temporal changes of the gravity field at large spatial scales. The International Gravity Field Service, an umbrella “level-2” IAG service (incorporating the International Gravity Bureau, International Geoid Service, International Center for Earth Tides, International Center for Global Earth models, and other future new services for, e.g., digital terrain models), would be a natural key element contributing to GGOS. Major parts of the work of the services would, however, remain complementary to the GGOS contributions, which focus on the long-wavelength components of the geopotential and its temporal variations, the consistent procedures for regional data processing in a unified vertical datum and Terrestrial Reference Frame, and the ensuring validations of long-wavelength gravity field data products. 相似文献
88.
WU Yongfu & XU Jiyao Laboratory for Space Weather Center for Space Science Applied Research Chinese Academy of Sciences Beijing China 《中国科学D辑(英文版)》2005,48(10)
Gravity waves play a significant role in establishing the large-scale circulation and structure of the middle atmosphere. Through gravity wave saturation proc-esses, such motions are believed to cause turbulence, resulting in divergence of momentum flux and the diffusion of heat and constituents in the meso-sphere[1,2]. The mechanisms that contribute signifi-cantly to the gravity wave saturation are thought to be the dynamical and convective instabilities[3]. However, it is difficult to distin… 相似文献
89.
Derek Blundell Nicholas Arndt Peter R. Cobbold Christoph Heinrich 《Ore Geology Reviews》2005,27(1-4):333
Metallogenic provinces in Europe range in age from the Archaean to the Neogene. Deposit types include porphyry copper and epithermal Cu–Au, volcanic-hosted massive sulphide (VMS), orogenic gold, Fe-oxide–Cu–Au, anorthosite Fe–Ti-oxide and sediment-hosted base-metal deposits. Most of them formed during short-lived magmatic events in a wide range of tectonic settings; many can be related to specific tectonic processes such as subduction, hinge retreat, accretion of island arcs, continental collision, lithosphere delamination or slab tear. In contrast, most sediment-hosted deposits in Europe evolved in extensional, continental settings over significant periods of time. In Europe, as elsewhere, ore formation is an integral part of the geodynamic evolution of the Earth's crust and mantle. Many tectonic settings create conditions conducive to the generation of water-rich magma, but the generation of ore deposits appears to be restricted to locations and short periods of change in temperature and stress, imposed by transitory plate motions. Crustal influence is evident in the strong structural controls on the location and morphology of many ore deposits in Europe. Crustal-scale fault–fracture systems, many involving strike-slip elements, have provided the fabric for major plumbing systems. Rapid uplift, as in metamorphic core complexes, and hydraulic fracturing can generate or focus magmatic–hydrothermal fluid flow that may be active for time spans significantly less than a million years. Once a hydrologically stable flow is established, ore formation is strongly dependent on the steep temperature and pressure gradients experienced by the fluid, particularly within the upper crust. In Europe, significant fracture porosity deep in the crystalline basement (1%) is not only important for magmatic–hydrothermal systems, but allows brines to circulate down through sedimentary basins and then episodically upward, expelled seismically to produce sediment-hosted base-metal deposits and Kupferschiefer copper deposits. Emerging research, stimulated by GEODE, can improve the predicting power of numerical simulations of ore-forming processes and help discover the presence of orebodies beneath barren overburden. 相似文献
90.