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2010年1月12日海地(Haiti)地区发生Mw 7.0地震,最终造成约31万人遇难,同年4月4日墨西哥南加州Baja地区发生Mw 7.2地震,2人遇难.Haiti地震的矩震级与Baja地震的矩震级相当,人员伤亡却远大于后者,其原因只是Haiti地区经济不发达,建筑物抗震设防标准低、抗震性能差吗?地震造成建筑物倒塌及人员伤亡程度并非仅仅取决于建筑物的抗震程度,一方面与其释放的地震波辐射能相关,另一方面则主要与发震后造成的强地面运动的大小有关.目前尚无两个地震完整的强震观测记录,尤其是Haiti地震,针对二者构建几何尺度相同的动态复合震源模型(DCSM),选取两个地震中分别主要人员伤亡的城市太子港及Mexicalia城作为强地面运动模拟的特征城市,对比其近断层强地面运动的差异.模拟结果表明,Haiti地震近断层区域强地面运动显著高于Baja地震的强地面运动,两个地震模拟的烈度特征分布图也显示出了明显的强地面运动的差异性.因此,Haiti地震造成发震区域内建筑物损毁程度及人员伤亡情况均严重于Baja地震,重要原因之一在于Haiti地震地震波辐射能大且造成的强地面运动强. 相似文献
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1988年11月6日,在云南省澜沧、耿马相继发生了7.6级、7.2级地震。这次地震前曾经作过准确的中长期预报。在1985年完成1986年出版的南北地震带未来十年地震危险性研究报告和预测图中,澜沧、耿马地区就是两个圈定的7级危险区中的一个。1986年该报告正式上报云南省人民政府。1987年起该区域为我省的地震危险性监视区。1988年除加强监视外,我们还加强了一系列大震对策措施的准备工作。1988年8月该区地震活动增强,我局派出的现场考察组向当地政府作了汇报,并指出该区仍存在着严重的地震危险性。与此同时,省局科技人员对该区作出了一系列不同程度的短期预报,并向当地打了招呼,当地政府采取了一定的措施。遗憾未能作出临震预报。大震发生后,我局昆明遥测台网仅7分钟定了位置和震级,并报告了国家地震局和省政府,及时为抗震救灾提供可靠的科学依据。震后2.5小时,现场监测队伍就出发了。在大震现场仅三天内就作出了地震趋势判断,也较好地作出了强余震的预报,有力地组织了地震考察及地震知识宣传。这一系列的大震对策工作极大地推动了现场的抗震救灾工作,减轻了震灾的继续发生及其带来的巨大的心理和社会影响。整个澜沧—耿马地震的预报、速报及大震对策工作在国内外都是一次较高水平的科学实践,得到了中央慰问团及 相似文献
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地震调查研究推动本部根据1998年1月9日推动本部决定和2006年2月17日修订后的《地震调查研究推进本部预算等事务调整意见》,就2008年度的地震调查研究预算概算要求,听取有关行政机关、独立行政法人、国立大学法人的意见,对2008年度地震调查研究预算作了调整,结果如下并于2007年8月31日公布。日本地震调查研究推动本部制定2008年度地震调查研究项目预算时,遵循和采取了以下方针和措施。(1)推动地震调查观测:推动基础调查观测(设置、维持与更新观测仪器),推动重点调查观测。(2)进一步提高地震发生可能性的长期评价、强震动预测等(概观全国地震… 相似文献
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尽管日本国土面积只占世界陆地的1%,但发生的地震却占全球地震总数的10%左右。尤其是致灾型大地震的发生率很高。为应对这一问题,日本政府自1965年开始推进地震预测研究计划,并经历了多个阶段的计划和修订。近年来,随着信息科学领域的快速发展,日本政府将信息科学引入到了地震科学研究,开展了《利用信息科学的地震研究》计划,旨在促进面向新地震预测科学的创新性研究。目前,日本地震调查本部对地震预测的总体观点“一定程度上可预测板间地震的发生时间,但现有研究仍无法预测未来地震,当前工作的重点是预测未来地震的震动规模”。地震预测的科学研究理念正从原先的“灾害发生的预测”向“灾害发展过程的预测”转变。 相似文献
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地震预报推进组 《地震地磁观测与研究》2001,22(4):16-31
地震预测首先是一个科学问题 ,地震预测的实现只能以科学研究为基础。十五年来 ,在中国地震局有关部门和国家自然科学基金会等机构的支持下 ,地球物理研究所科研人员围绕与地震预测的有关的科学问题 ,开展了多方面的基础研究和应用研究。这些研究工作可以概括为 3个方面。1 地震活动性分析及其在地震预测研究中的应用我国有着丰富的历史和现代地震目录。地震活动性研究是我所地震预测研究中最重要的工作之一 (许绍燮等 ,1 989,1 990 ;许绍燮 ,1 993 ;Wang等 ,1 996;郑秀芬等 ,1 998;王林瑛 ,1 999)。地震活动性的经验性研究包括强地震活动… 相似文献
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1 2 0 0 1年度政府有关地震调查研究的预算总额约为 1 60亿日元 地震调查研究推进本部的统计结果表明 ,2 0 0 1年度政府有关地震调查研究的预算比上一年度减少约 4亿日元 ,总额为 1 60 .41亿日元。本年度预算将用于以下几个方面 :1 )为实现地震调查委员会 2 0 0 4年制成地震动预测图的目标 ,防灾科学技术研究所着手研究新的制作方法。2 )在有关地震的地基调查观测设施方面 ,防灾科学技术研究所还将不断添置高灵敏度地震观测设施和宽频带地震计。3 )政策委员会调查观测计划分会将建立一种更完善的高精度地震观测数据的流通体制。在上一… 相似文献
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日本活断层研究中心简介 总被引：1，自引：1，他引：1
《日本地震学会新闻通讯》 《国际地震动态》2002,(3):26-27
发生在 6年前 1 995年 1月 1 7日的兵库县南部地震 ,造成了巨大的损失 ,人们对此仍记忆犹新。由于该地震是由内陆活断层运动诱发的大城市圈直下型地震 ,因此 ,引起了社会各界对于活断层的极大关心。虽然那时已知日本存在的活断层为数甚多 ,据说有 2 0 0 0余条 ,但现在回想起来 ,这一信息并未能在区域地震防灾中充分发挥作用。为此 ,日本组建了地震调查研究推进总部 (文部科学省 ) ,希望能在该总部的领导之下 ,进一步推动对活断层等的调查研究 ,并以新获取的高精度信息为基础 ,评估未来发生地震的危险性 ,开展区域性的震害预测。活断层研究中… 相似文献
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青海省1990年以来地震大形势预测成果分析和探讨 总被引：1，自引：1，他引：0
对1990年以来青海省年度会商报告进行了统计分析,发现1994～2001年度的地震大形势预测结果基本与实际地震情况一致,而2002～2005年度的预测结论与实际发生的地震有一些背离。经分析认为,这可能与该时段的强地震活动情况较弱有关。2006～2008年度地震大形势的预测工作又获得了较为可喜的业绩,表明该方面研究人员具有很强的专业性和分析预测能力,体现了青海省地震局在地震大形势研究工作中作出了值得肯定的成绩。同时,也说明地震大形势预测工作是一项复杂且综合性很强的研究工作,需要一批知识面广,专业背景相对宽的研究人员来做综合性的研究。 相似文献
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现今 ,人们把地震预报与防灾对策比喻成汽车两侧的轮子。自 1 96 2年《日本的地震预报现状及推进计划》草案发表后 ,美国、前苏联的研究取得了显著的进展。中国 1 975年海城大地震的成功预报震惊了整个世界。在地震预报由研究阶段迈入实用阶段的时候 ,日本颁布了“大规模地震对策特别措施法” (大震法 ,1 978) ,这是以预报为前提 ,首次将灾害对策立为国家的法律。但是 ,由于 1 992年虽已作出警报但却以失败告终的美国加州帕克菲尔德地震 ,以及 1 995年兵库县南部地震没能作出临震预报这 2个失败的例子 ,使人们误以为地震预报研究确确实实到… 相似文献
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In this paper, the changes in sediment transport over 51 years from 1955 to 2006 in the Kuye River in the Loess Plateau in China are assessed. Key factors affecting sediment yield and sediment transport, such as precipitation depth, discharge, and human activities are studied. To investigate the changes in sediment yield in this watershed, a trend analysis on sediment concentration, precipitation depth, and discharge is conducted. Precipitation depths at 2 Climate Stations （CSs）, as well as discharge and sediment transport at 3 Gauging Stations （GSs） are used to assess the features of sediment transport in the Kuye River. The rtmoff modulus （defined as the annual average discharge per unit area, L/（s·km^2）） and the sediment transport modulus （defined as the annual suspended sediment transport per unit area, t/（yr km^2）） are introduced in this study to assess the changes in runoff and sediment yield for this watershed. The results show that the highest average monthly discharge during the study period in the Kuye River is 66.23 m^3/s in August with an average monthly sediment concentration of 88.9 kg/m^3. However, the highest average monthly sediment concentration during the study period in the Kuye River is 125.34 kg/m^3 and occurs in July, which has an average discharge of 42.6 m^3/s that is much less than the average monthly discharge in August. It is found that both the runoff modulus and sediment transport modulus at Wenjiachuan GS on the Kuye River has a clear downward trend. During the summer season from July to August, the sediment transport modulus at Wenjiachuan GS is much higher than those at Toudaoguai and Longmen GSs on the Yellow River. The easily erodible loess in the Kuye River watershed and the sparse vegetation are responsible for the extremely high sediment yield from the Kuye River watershed. The analyses of the grain size distribution of suspended load in the Kuye River are presented. The average monthly median grain size of suspended load in the Kuye River is largest in February and then decreases until June. In July, the average monthly median grain size of suspended load approaches another peak and decreases until September. Then, the median grain size of suspended load starts to increase until February of the following year. However, the average monthly median grain size of suspended load in the Yellow River at Toudaoguai and Longmen GSs is the smallest between early summer and late fall The median grain size in the Yellow River starts to increase in November and approaches the largest size in January. 相似文献
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3He/4He ratios up to 3.5 times the ratio of atmospheric He were found in groundwater samples. The3He enrichment can be attributed to radiogenic3He produced by in-situ beta-decay of3H. This shows that tritiogenic3He is accumulating in confined waters. From tritiogenic3He and3H concentrations, ages of groundwaters can be calculated. Detection of tritiogenic3He gives a tool to trace a tritium contamination which occurred in the past and cannot be assessed only by the3H counting method. 相似文献
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The aim of this study is to estimate likely changes in flood indices under a future climate and to assess the uncertainty in these estimates for selected catchments in Poland. Precipitation and temperature time series from climate simulations from the EURO-CORDEX initiative for the periods 1971–2000, 2021–2050 and 2071–2100 following the RCP4.5 and RCP8.5 emission scenarios have been used to produce hydrological simulations based on the HBV hydrological model. As the climate model outputs for Poland are highly biased, post processing in the form of bias correction was first performed so that the climate time series could be applied in hydrological simulations at a catchment-scale. The results indicate that bias correction significantly improves flow simulations and estimated flood indices based on comparisons with simulations from observed climate data for the control period. The estimated changes in the mean annual flood and in flood quantiles under a future climate indicate a large spread in the estimates both within and between the catchments. An ANOVA analysis was used to assess the relative contributions of the 2 emission scenarios, the 7 climate models and the 4 bias correction methods to the total spread in the projected changes in extreme river flow indices for each catchment. The analysis indicates that the differences between climate models generally make the largest contribution to the spread in the ensemble of the three factors considered. The results for bias corrected data show small differences between the four bias correction methods considered, and, in contrast with the results for uncorrected simulations, project increases in flood indices for most catchments under a future climate. 相似文献
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Observations of trace gases (SO2, NH3, NO2 and O3) were made during the period 1981 to 1984 at 6 different locations representative of urban industrial, urban, nonurban, thermal power plant and marine environment. Diurnal variations of the trace gases were studied in an urban environment. Except in the urban industrial environment, the concentration of NH3 was found in the range of background values. Also, the average concentrations of NO2 and O3 at the different environments were in the order of background values. However, the concentrations of SO2 were substantially higher by about 7 times, in urban industrial and thermal power plant environments. The diurnal variations of SO2, NH3 and NO2 showed anitphase relationship with surface temperature at the urban environment station which is relatively free of industrial pollution. Discussion is centred on trace gas variations in different environments in India together with the values reported for various countries in the world. 相似文献
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Cu concentrations in surface (river and lake) and subsurface waters are determined. The geographic pattern of Cu distribution in natural water is identified. This pattern is controlled by the difference between its concentrations in drained rocks and soils and the geochemical redox conditions of its migration. Territories with low, medium, and elevated Cu concentrations in natural waters are identified. The concentrations of Cu in natural waters of the region are found to be generally lower than the Clarke values. 相似文献
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Changes in thermal extremes of the climate of Poland in 1951–2010 are examined. Warm extremes have become more frequent, while cold extremes have become less frequent. In the warming climate of Poland, the increase in the number of extremely warm days in a year and the decrease in the number of extremely cold days in a year have been observed. Also the increase of the maximum number of consecutive hot days in a year and the decrease of the maximum number of consecutive very cold and extremely cold days in a year have been observed. However, the trends are not of ubiquitous statistic significance, as the natural variability is strong. 相似文献
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M. MONIRUL QADER MIRZA 《水文科学杂志》2013,58(5):613-631
Abstract The basin area of the Ganges River in Bangladesh is extremely dependent on a regular water supply from upstream to meet requirements for agriculture, fisheries, navigation, salinity control, and domestic and industrial sectors. In 1975, India commissioned a barrage on the Ganges River at Farakka to divert a significant portion of the dry season flow in order to make the Calcutta Port navigable. Statistical analyses of discharge and water level data have been carried out to determine if significant changes have occurred in the hydrology of the Ganges system in Bangladesh in the post-Farakka period. Siltation of the Gorai River (an offtake of the Ganges River) has also been examined using the stage-discharge relationship and regression analysis. The analyses show that the diversion has caused considerable hydrological changes in the Ganges system in Bangladesh. The water supply in the dry season has been reduced substantially, while siltation of the Gorai River has increased significantly. 相似文献
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Resistivity techniques have been used successfully to identify and delineate geothermal resources in Iceland. The most frequently used techniques include Schlumberger, central loop TEM and head-on profiling. Geothermal systems in Iceland are located both within and outsite the active volcanic regions. Outsite the active volcanic regions the temperature in the upper most kilometer of the geothermal systems is below 150° C whereas the temperature in the geothermal fields within the active volcanic regions exceeds 200° C. The resistivity of the rock in geothermal fields located outside the active volcanic regions ranges from about 10 m to some hundreds of m, and are characterized by considerably lower resistivity than of the surrounding rocks. Most of the geothermal systems within the active volcanic regions, show common resistivity structure with low resistivity of 1–5 m surrounding an inner core of higher resistivity. This increasing resistivity with depth is associated with a change in the conduction mechanism, from interface conduction to electrolyte conduction due to a change in alteration minerals at about 240° C. Examples of resistivity surveys of geothermal fields from both outsite and within the active volcanic regions are discussed. 相似文献