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矿物中的流体包裹体记录了地球古流体的形成和演化、矿物的形成环境等各种地质信息。利用微区微量测量技术测定断裂带脉石矿物流体包裹体可以获得断层和地震活动的信息,延长认识地震复发周期的时间,对确定地震活动规律有重要意义。迄今为止,地震流体研究主要是关于宏观区域流体(水和气体)变化规律及其与地震的关系,对微区微量流体的研究很少。本文扼要介绍了地震和构造活动中流体作用与流体包裹体拉曼光谱测量技术,综述了流体包裹体(FI)分析在地震与断裂活动方面的研究进展,并提出了进一步研究的领域,以期促进微区微量地震流体研究和应用。 相似文献
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随着断层面形貌测量、宇宙成因核素测年等技术的发展,基岩断层面成为在基岩区古地震研究的良好研究对象。但是,受沟谷侵蚀、沉积覆盖和人为改造等非构造因素影响,并非所有出露的基岩断层面都能完整记录和保存古地震信息。因此,必须在基岩断层面上选择合适的研究点。传统的野外测量方法耗时费力,难以掌握基岩断层面的整体信息,即使通过高分辨率卫星影像也无法获得基岩断层面的精细结构。小型无人机航测(sUAV)采用低空摄影测量技术,可快速获取基岩断层面高精度的地表三维结构,为筛选目标工作点提供便利。文中以山西地堑系六棱山北麓断裂的马家窑基岩断坎为例,采用小型无人机航测结合SfM摄影测量技术,获得了基岩断层面的高精度三维地形数据,通过精细地貌解译和断层坎剖面分析识别了沿断层坎分布的崩塌破坏、沉积埋藏和侵蚀剥露等非构造因素,分析了侵蚀、埋藏和构造这3种典型的基岩断层面的形态特征,选取了适合开展古地震研究的基岩断层面点,展现了小型无人机在基岩区古地震研究工作中发挥的重要应用潜力。 相似文献
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通过延怀盆地构造背景、新构造活动、古地震等资料的分析,综合构造应力场模拟、构造类比、大震离逝率、孕震蓄能等因素及由经验公式推断的研究结果,对延怀盆地设定地震相关参数进行了研究.结果表明,延怀盆地设定地震的震级上限为7,发震断层为方家冲一营门矿段断层,震源深度为10 km左右. 相似文献
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地震危险区的边界划分探讨 总被引:1,自引:0,他引:1
本文针对目前地震危险区边界划分上存在的问题,从地震地质和地震构造的角度,结合测震学方法进行了分析,指出地震分布和地震危险区边界划定与活动构造有密切的联系。依据这一思想,阐明了构造活动与地震活动的关系,初步提出了地震危险区边界判析的原则,即把地震危险区限制在一定的地震构造区(带);其边界依据活动构造划定;在地震危险区内部进行发震构造条件研究,并对这些发震构造(活断层)进行活动度分析;分层次地对地震危险区范围及其危险度进行确定。 本文着重进行了活动构造的研究,对中国大陆的活断层、新生代盆地、地形面以及古地震等作了活动时代、活动性质、活动强度等多方面的论述。 相似文献
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在活动构造研究中,开挖探槽,发现隐藏于地下的古地震活动迹象是一项重要的突破。通过详细论述探槽方法研究古地震的原理及选点布槽、设计开挖、探槽记录、采集年龄样品等环节,较系统地总结了探槽研究古地震的整个工作流程。 相似文献
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后差分GPS测量则木河断裂地震微地貌特征 总被引:4,自引:0,他引:4
地震微地貌是研究古地震的重要证据。 发生在则木河断裂带上的1850年地震的地表破裂带在人类活动较少的地区得以保存完好。 研究区内地形起伏大, 断塞塘、 断层陡坎、 鼓包等微地震地貌特征明显, 在三维视图内可直观反映测量区内的这些地貌特征。 利用后差分GPS方法测量断裂活动形成的地震微地貌, 水平测量精度可达0.5 m, DEM精度可到一个像元1 m, 是定量化研究地震微地貌的一种新方法。 测量结果表明, 大箐梁子顶部七条干沟对应多次古地震事件; 大箐梁子顶部鼓包被断裂断错, 断塞塘沉积区向南迁移, 鼓包最新断错约4 m, 大箐村南山坡形成50 cm高断层陡坎。 说明大箐梁子一带地震活动性较强, 且以挤压构造为主。 相似文献
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《国际泥沙研究》2014,(4)
正Director:Shangfu Kuang,China Vice-directors:Chunhong Hu,China Duihu Ning,China Guangquan Liu,China The International Research and Training Center on Erosion and Sedimentation(IRTCES)was jointly set up by the Government of China and UNESCO on July 21,1984.It aims at the promotion of international exchange of knowledge and cooperation in the studies of erosion and 相似文献
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《中国科学:地球科学(英文版)》2014,(3)
正SCIENCE CHINA Earth Sciences,an academic journal cosponsored by the Chinese Academy of Sciences and the National Natural Science Foundation of China,and published by Science China Press and Springer,is committed to publishing high-quality,original results in both basic and applied research. 相似文献
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Richard D. Hey 《地球表面变化过程与地形》1979,4(1):59-72
Feedback mechanisms, which operate upstream through drawdown and backwater effects and downstream through sediment discharge are responsible for channel evolution. By combining these mechanisms with channel processes it euables a dynamic process-response model to be developed to simulate the initial evolution of straight gravel-bed channels. When erosion commences on a land surface, sediment entrained in the headwater reach by hydraulic action is selectively transported, deposited and reworked. This produces a damped oscillation between degradation and aggradation as the channel and valley respond to spatial and temporal variations in sediment calibre and hydraulic conditions. The initial cut and fill phases are responsible for valley incision and floodplain development while secondary and subsequent activity can produce river terraces. Eventually sediment entrainment in the headwaters declines as slopes are reduced. Subsequent channel evolution is relatively insignificant because it is dependent on local weathering activity producing material that can be transported on declining slopes. Therefore landforms produced during the initial phase of development, when local weathering was non-limiting, dominate the landscape. 相似文献
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Based on relocating the Jiujiang-Ruichang earthquake sequence which occurred on November 26, 2005 in Jiangxi Province with the double-difference (DD) algorithm and master event technique, the paper discusses the focal mechanism of the main shock (MsS.7) and the probable seismo-tectonics. The precise relocation results indicate that the average horizontal error is 0.31kin in a EW direction and 0.40kin in a NS direction, and the average depth error is 0.48kin. The focal depths vary from 8kin to 14kin, with the predominant distribution at 10kin - 12kin. The epicenter of the main shock is relocated to be 29.69^oN, 115.74^oE and the focal depth is about 10.Skin. Combining the predominant distribution of the earthquake sequence, the focal mechanism of the main shock and the tectonic conditions of N-E- and NW-strike faults growth in the seismic region, we infer that the main shock of the earthquake sequence was caused by a NW striking buried fault in the Rnichang basin. The nature of seismic faults needs to be further explored. 相似文献
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《水文科学杂志》2013,58(6)
Abstract The western reservoirs represent the principal groundwater system in Morocco. Demographic, industrial and agricultural developments during the last decade have markedly altered groundwater quality. The Mamora coastal aquifer system is among the Atlantic systems which are most heavily threatened by pollution. Agricultural and industrial activities, and rapid urban growth contribute to the pollution of the groundwater. Contamination transport is facilitated by a high permeability of the aquifer formations. In order to assess the actual groundwater quality of the Mamora aquifer and to understand the influence of the factors generating the pollution, an extensive multidisciplinary research programme is in progress, with hydrochemistry and microbiology playing essential roles. The present paper concerns the spatial distribution of physico-chemical parameters in the groundwater, subjected to domestic, industrial and agricultural pollution. Fifty-seven samples were analysed for several parameters (Ca2+, Mg2+, Na+, K+, Cl?, SO4 2?, HCO3 ?, NO3 ?, pH, electrical conductivity and temperature). The microbiological analysis of 143 samples reveals the presence of four kinds of indicator bacteria in the groundwater resources: faecal Streptococci, faecal coliform, Escherichia coli and Clostridium. The physico-chemical results and bacteriological monitoring show that the nitrate and bacteria concentrations exceed the maximum admissible levels, notably around pumping stations in the sectors of Sidi Taibi, Sidi Ahmed Taleb and Aïn Sbaâ. Contamination is generated by uncontrolled anthropogenic activities and accentuated by the high intrinsic vulnerability of the aquifer system. Several parameters appeared to exceed admissibility standards. Measures are recommended to prevent groundwater pollution in the region. 相似文献
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《中国科学:地球科学(英文版)》2014,(12)
正SCIENCE CHINA Earth Sciences,an academic journal cosponsored by the Chinese Academy of Sciences and the National Natural Science Foundation of China,and published by Science China Press and Springer,is committed to publishing high-quality,original results in both basic and applied research. 相似文献