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151.
为了研究华北地区近年地壳水平运动的状态与演化.利用10a来华北地区网络工程、山西断裂带GPS观测成果.结合该区地质构造背景.分析了华北地区各块体运动的方向、速率变化及其与区内所发生地震的关系.初步得出以下结论:在区域应力场相对稳定时,表现为区域内GPS观测点整体趋势性运动不明显;而在区域应力场相对变化时.表现为影响区域内GPS观测点出现明显的整体趋势性运动。  相似文献   
152.
王道 《内陆地震》2004,18(1):45-55
重点分析了新疆及边邻地区1980年以来6次7级以上地震前后北天山地下流体动态异常资料,其中3次地震前地下水有短期前兆异常变化,震时同震地震波效应普遍存在,震后异常十分突出且幅度大;以水位为主的水动力学效应反映了大区域应力调整过程具有不可逆特征。水文地球化学参数的变化不敏感。讨论了地下水远程效应与井震距离的关系以及阶跃异常的幅度等问题。  相似文献   
153.
Geologic marks related to extraterrestrial impact events, such as impact split gravels, impact brecciate layers, impact dikes, microirghizites, microtektites, especially meteoritic residues, were discovered on the boundary between Sinian/Cambrian at Tianmenshan of Western Hunan, which may possibly demonstrate that an extraterrestrial impact event has ever occurred there on the S/C boundary.  相似文献   
154.
玉米淀粉废水回收及处理研究   总被引:1,自引:1,他引:1  
采用调节等电位点—超过滤组合技术对玉米淀粉废水的资源回收和处理进行研究,确定了最佳工艺参数。结果表明通过调节等电位点,可回收粗蛋白用作家禽饲料,同时废水中的CODcr、TSS和BOD5去除率分别可达48.8%、49.6%和27.2%以上,减轻了后续超过滤处理压力;通过超过滤进一步处理,出水COD、TSS和BOD去除率分别达91.3%、92.5%和95.1%。  相似文献   
155.
Basin-fill sequences of Mesozoic typical basins in the Yanshan area, North China may be divided into four phases, reflecting lithosphere tectonic evolution from flexure (T3), flexure with weak rifting (J1+2), tectonic transition (J3), and rifting (K). Except the first phase, the other three phases all start with lava and volcaniclastic rocks, and end with thick coarse clastic rocks and/or conglomerates, showing cyclic basin development rather than simple cyclic rift mechanism and disciplinary basin-stress change from extension to compression in each phase. Prototype basin analysis, based on basin-fill sequences, paleocurrent distribution and depositional systems, shows that single basin-strike and structural-line direction controlling basin development had evidently changed from east-west to northeast in Late Jurassic in the Yanshan area, although basin group still occurred in east-west zonal distribution. Till Early Cretaceous, main structural-line strike controlling basins just turned to northeast by north in the studied area.  相似文献   
156.
The west Kunlun fold-thrust belt (WKFTB) and the Altun fold-thrust belt (AFTB) are respectively located in the southern margin of the Tarim basin, NW China. The analyses of typical structures and regional dynamics of the fold-thrust belts reveal their different structural and petroleum features and mechanisms. WKFTB differs from AFTB by abundant fault-related folds and triangles zones, and was formed by northward extrusion of the west Kunlun orogen. AFTB was affected synchronously by northward extrusion of the Altun orogen and the sinistral strike-slipping of the Altun Fault, so it is characterized by the minor scale and the monotonous structural styles. The Aqike anticline and the Aqike fault, of which the strikes are orthogonal to the strike of the fold-thrust belts, are regarded as the adjustive structures between both of the fold-thrust belts. The oil-gas pools of WKFTB develop mainly in the faulted-related anticline traps, but the oil-gas pools of AFTB develop mainly in the low fault-block and anticlines traps related with the paleo-uplifts. There are different exploration countermeasures for both of the fold-thrust belts.  相似文献   
157.
The superimposed basin must have undergone the changes of regional stress field. Study on the nature and switch of regional stress field of superimposed basin is very useful to understanding its stress state and tectonic events during its formation and evolution. As sensitive markers of small stress changes, joint and shear fracture, characterized by consistency of orientation over wide area, can be used to reconstruct paleostress state and its evolution. Detailed observations and analysis on the orientations, geometrical patterns, sequences of joints and shear fractures and their chronological relation to faults and folds show that, the NEE-SWW systematic joints and NNW-SSE systematic joints developed in the Mesozoic and Cenozoic strata are much more prominent than NW-SE systematic joints and shear fractures with different orientations. And the NWW-SEE and NW-SE systematic joints formed later than NEE-SWW systematic joints but earlier than shear fractures with different orientations. According to the relationships between joint and shear fractures and stress, the NEE-SWW systematic joints are inferred to result from lateral weak extension caused by the late Cretaceous regional uplift, while the NNW-SSE and NW-SE systematic joints are interpreted as syn-tectonic deformation relating to strong N-S compression in the Neogene. But some conjugate shear fractures occur probably due to sinistral strike-slip faulting in the Kuqa depression. At the beginning of the Neogene, the stress field changed and the maximal principal stress σ1 switched from vertical to horizontal.  相似文献   
158.
Introduction Through many year's practices by vast numbers of scientific and technological workers andefforts from all aspects, the dynamic testing method of high-low strain has formally entered intothe technical code of foundation pile test of construction at last (The Industry Standards of thePeople's Republic of China, 2003). The striking mode of the dynamic testing method of high strainis stipulated as hammer in the code, the striking of rocket can also be used. The latter is widely…  相似文献   
159.
Sampling is to, by efficient selection of samples, acquire the accurate information about the population (the research object) at less cost. Spatial sampling is a kind of sampling toward geospatial objects or features with spatial correlation. The differences between effi-cient sampling and completely universal survey lie in quality, time and cost. Sampling provides a kind of economical, prompt and accurate survey[13]. Efficient spatial sampling can be regarded as the optimization of the sampl…  相似文献   
160.
小波分析思想在中尺度对流活动研究中的应用   总被引:4,自引:1,他引:4  
应用近些年在大气科学领域被广泛采用的小波分析方法,基于小波分析思想提取GMS红外卫星云图中的中-β尺度对流云信息,分析中-β尺度对流活动特征.构造了理想小波函数模板,对四种理想云模型进行了实验分析,建立了小波变换提取云的中心位置和水平尺度等信息的方法.并应用该方法对中-β尺度对流活动实例进行分析和追踪实验.此外,还应用小波分析方法对2001年夏季(6~8月)我国中、东部地区的中-β尺度对流活动进行了统计分析,揭示出了这一区域中-β尺度对流活动的分布规律、强度变化等特征.  相似文献   
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