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中国数字地震台网(CDSN)经过第3期升级改造后,硬件系统性能有了质的飞跃,设备的可维护性及数据稳定性全面提升,系统的复杂程度也逐渐攀升。本文详细介绍CDSN技术系统的构成及升级过程,阐述技术规范和实施细节及对CDSN技术改造发挥的作用。 相似文献
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中国数字地震台网(CDSN)是我国第一批现代化的,具有国际水平的优秀台网,对我国乃至世界的数字地震学的发展都有一定的贡献.数字地震仪的高速发展,不仅使地震科研发生了质的变化,而且有力地推动了地震台站工作的计算机化,通信技术的现代化;也使得数字台站的工作发生了较大的改变,从传统的工作方式变到数字方式.CDSN牡丹江台站运行十多年来,已积累了许多经验,台站的每一个工作人员都能感到数字仪有着模拟仪器所根本达不到的先进性能.为了早日利用数字地震图,从1999年10月起牡丹江台按照CD-SN技术管理中心的要求,开始了数字图与模拟图的分析对比观测工作.我们认为,为了减少重复性工作,避免经济浪费,同时也降低劳动强度,提高地震资料的使用效率,用数字地震仪分析处理数字地震图是台站未来发展的方向,在技术上也是完全可行的. 相似文献
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中国数字地震台网(CDSN)1997年以来承担我国国内及周边国家发生较大地震的地震矩张量震源参数速报任务,以中国地震局测定的震中参数为基准,用CDSN台站记录的数字波形资料反演地震的震源参数,将结果上报给中国地震局。同时在CDSN的网 相似文献
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中国数字地震台网 (CDSN)地震事件数据库系统是一个数据服务软件系统。它以国际著名的 ORACLE数据库为开发环境 ,以 CDSN数字地震事件数据为基础 ,借鉴 IRIS等国际地震学机构优秀的数据服务方式 ,利用 rdseed、 SAC等地震学领域流行的数字软件 ,为网上用户共享 CDSN数字地震数据提供了一个全新的服务窗口。本文对该数据服务软件系统及分布数据库系统作相关的介绍。 相似文献
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根据中国地震局地球物理研究所中国数字地震台网数据管理中心 (CDSN DMC)从美国地震学合作研究会数据管理中心 (IRIS DMC)得到的资料 ,1 999年 1 2月份全球范围内共发生 M≥ 5 .0地震 1 2 7次 (见表 1 )。其中 M≥ 6.0地震 1 9次 ,最大的一次地震发生在菲律宾的吕宋 ,震级为 7.3。本月发生的 1 2 7次 M≥ 5 .0地震中有 84次发生在东半球 ,43次发生在西半球。根据中国数字地震台网记录统计 ,对于发生在我国境内的 M≥ 5 .0的地震事件 ,CDSN大部分台站有地震波形记录 ;对于发生在全球的 M≥ 6.0的地震事件 ,CDSN各台站也有地震波形… 相似文献
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根据中国地震局地球物理研究所中国数字地震台网数据管理中心 (CDSN DMC)从美国地震学合作研究会数据管理中心 (IRIS DMC)得到的资料 ,2 0 0 1年 1月全球范围内共发生 M≥ 5 .0地震 12 4次 (见表 1)。M≥ 7.0地震 5次 ,其中最大的一次发生在印度 ,震级为 8.0。本月发生的 12 4次 M≥ 5 .0地震中有 78次发生在东半球 ,46次发生在西半球。根据中国数字地震台网记录统计 ,对于发生在我国境内的 M≥ 5 .0的地震事件 ,CDSN大部分台站有地震波形记录 ;对于发生在全球的 M≥ 6 .0的地震事件 ,CDSN各台站也有地震波形记录。欢迎各研究单… 相似文献
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根据中国地震局地球物理研究所中国数字地震台网数据管理中心 (CDSN DMC)从美国地震学合作研究会数据管理中心 (IRIS DMC)得到的资料 ,2 0 0 0年 1 2月全球范围内共发生 M≥ 5 .0地震 95次 (见表 1 )。其中 M≥ 7.0地震 1次 ,发生在土库曼斯坦 ,震级为 7.5。本月发生的 95次M≥ 5 .0地震中有 5 8次发生在东半球 ,37次发生在西半球。根据中国数字地震台网记录统计 ,对于发生在我国境内的 M≥ 5 .0的地震事件 ,CDSN大部分台站有地震波形记录 ;对于发生在全球的 M≥ 6 .0的地震事件 ,CDSN各台站也有地震波形记录。欢迎各研究单位使… 相似文献
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根据中国地震局地球物理研究所中国数字地震台网数据管理中心 (CDSN DMC)从美国地震学合作研究会数据管理中心 (IRIS DMC)得到的资料 ,2 0 0 0年 1月份全球范围内共发生 M≥ 5 .0地震 94次 (见表 1 ) ,其中 M≥ 6.0地震 1 6次 ,M≥ 7.0地震 1次 ,最大的一次地震发生在汤加群岛 ,震级为 7.2。本月发生的 94次 M≥ 5 .0地震中有 61次发生在东半球 ,3 3次发生在西半球。根据中国数字地震台网记录统计 ,对于发生在我国境内的 M≥ 5 .0的地震事件 ,CDSN大部分台站有地震波形记录 ;对于发生在全球的 M≥ 6.0的地震事件 ,CDSN各台站也… 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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K.-G. Malle 《洁净——土壤、空气、水》1992,20(4):196-204
Zinc in the Environment. In 1990 the world production of zinc ammounted to 7 Mio. metric tons. The main areas of application were: galvanization, alloys like brass and zinc metal. The content in the earth crust varies between 10–300 ppm zinc with a mean of 70 ppm. Uncontaminated surface waters contain less than 10 mg/m3 zinc. Apart from civilization air contains 1–10 ng zinc per m3. These background concentrations are exceeded by orders of magnitude in zinc deposit areas and where anthropogenic influences predominate. Accumulation can occur in sediments and sewage sludge. Molluscs and Algae also accumulate zinc. Zinc is essential for live. With normal food the zinc supply of man is just sufficient. Bioaccumulation of zinc towards man or chronic oversupply of man is not known. Zinc has no teratogenic or mutagenic effects, a suspicion on a carcinogenic effect proved wrong. In stockbreeding and plant cultivation a minimum supply of zinc is necessary. Plants are relatively less sensitive against higher soil contents of zinc. Considering the toxicological and ecotoxicological effects of zinc in the environment, the critical organismens are marine invertebratae like tubifex, daphnia, gammarus and algae. But normally only a minor part of the total zinc contest is biologically available, depending on salt content and pH of the waters. 相似文献