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1.
地震目录(1994年3—5月)陈培善(中国北京100081北京国家地震局地球物理研究所)中国及邻区地震目录(1994年3—5月,M≥4.7)全球地震目录(1994年3─5月,M≥6)地震目录(1994年3—5月)@陈培善$北京国家地震局地球物理研究所...  相似文献   

2.
林蓉辉 《地震研究》1999,22(4):419-427
云南是中国地震活动最为频繁的省份之一。在1995年7月于1996年2月的7个月期间,接连发生了3次大地震,它们是,1995年7月12日孟连地震(M=7.3);1995年10月24日武定地震(M≡6.5),和1996年2月3日丽江地震(M≡7.0)。本在对上述3次地震作简单介绍的同时,将重点强调孟连地震的短临预报及社会响应能力。孟连地震是一次前震-主震-余震型地震,发震时刻为1995年7月12日0  相似文献   

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分析了华北地区1484年以来M≥5级地震平静现象:(1)华北地区1484-1730年及1815年以来2个地震活动期所有M≥5级地震平均平静时间为17.8个月,1731-1814年地震平静期的所有5级地震的平均平静时间约90.1个月,二者有明显差异;(2)华北地区2个地震活动期中相邻活动幕的幕间M≥5地震平均平静时间约86.4个月,与地震平静期大体一致,这样,90个月可以为华北地区M≥5级地震长期平静的标志性时间;(3)当前华北地区M≥5级地震平静时间达77个月,已接近长期平静的标志性时间,发生5级地震以上地震的可能已经很大;(4)上述工作成文后发生了2013年1月23日辽宁省辽阳市与沈阳市交界处5.1级地震,应注意华北进入新的地震活动幕。  相似文献   

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“东南亚地震构造与地震危险性国际讨论会”概况陈运泰,高文学(国家地震局地球物理研究)(国家地震局地质研究所)李京(国家地震局分析预报中心)“东南亚地震构造与地震危险性国际讨论会”于1994年1月27日至2月4日在越南河内举行。会议由越南国家科学研究中...  相似文献   

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华南地区M_L≥3.0级地震目录(1994年7~9月)注;台湾海峡地震序列取*。>屯0地震人编。(胡瑞贺汇编)华南地区M_L≥3.0级地震目录(1994年7~9月)@胡瑞贺...  相似文献   

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1996年5月全球M≥5.0地震动态1996年5月全球范围内共发生M≥5.0地震54次(见附表)。与上月相比全球地震活动有所减少,其中M≥6.0地震7次,最大的一次地震是5月2日13时34分(UTC)发生在所罗门群岛的6.5级地震。5月份的54次地震...  相似文献   

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对公元849年振武、天德地震史料进行了考证,认为:①地名“河西”是指唐代河西县,在今陕西合阳县黄河沿岸地区。②“云迦”是指唐代“云迦关”,可能在今包头西北石门附近。③这次地震“压死者数千人”。利用考证后的史料,对这次地震基本参数进行了再校订,确定这次地震为公元849年10月24日包头东河(40.6°N,110.1°E)7?级地震。   相似文献   

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希腊北部发生6.6级强烈地震1995年5月13日在希腊北部发生强烈地震,造成财产的较大损失。1.震源参数(1)发震时间1995年5月13日当地时间上午11时47分;格林尼治时间5月13日08时47分。(2)震级雅典地震研究所测定为里氏6.6级。(3)...  相似文献   

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1994年全球地震活动属于高水平,有4次大深震和4次浅源大地震。全球全年共发生6级以上地震134次,超过1993年。全球地震活动中心仍在太平洋西北边缘地震带。10月4日的千岛群岛地震是最大的浅源地震;6月9日的玻利维亚地震是最大的深源地震。1994年全球地震活动开始转折,揭开强烈活动期的序幕。各大地震带的A(b)值几乎按同一比例上升,显示全球地震整体性增强。全球地震A(b)值在6月和10月有两次高  相似文献   

10.
1995年7月12日中缅边境7.3级地震概况1995年7月12日在云南省孟连县中缅边境发生强烈地震,造成生命财产重大损失。1.震源参数(1)发震时间1995年7月11日格林尼治时间21时46分;北京时间7月12日05时46分。(2)震级我国地震台网测...  相似文献   

11.
Abstract

A new method is presented to generate stationary multi-site hydrological time series. The proposed method can handle flexible time-step length, and it can be applied to both continuous and intermittent input series. The algorithm is a departure from standard decomposition models and the Box-Jenkins approach. It relies instead on the recent advances in statistical science that deal with generation of correlated random variables with arbitrary statistical distribution functions. The proposed method has been tested on 11 historic weekly input series, of which the first seven contain flow data and the last four have precipitation data. The article contains an extensive review of the results.

Editor D. Koutsoyiannis

Citation Ilich, N., 2014. An effective three-step algorithm for multi-site generation of stochastic weekly hydrological time series. Hydrological Sciences Journal, 59 (1), 85–98.  相似文献   

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Abstract

In the Southwestern intermountain and high plains areas, precipitation is seasonal, with the major part of the rainfall occurring in the summer. Most winter precipitation occurs as low-intensity rain or snow along slow-moving cold fronts. Most summer precipitation occurs as short-duration, high-intensity thunderstorms from purely convective buildup or from convective cells developing along a weak fast-moving cold front. Almost all runoff occurs from the summer convective storms.

Since runoff-producing precipitation is of primary interest at the Southwest Watershed Research Center, Agricultural Research Service, Tucson, Arizona, the convective storms have been most thoroughly analyzed. Duration, intensity, areal extent, movement, character, and return frequencies for varying volumes and intensities of these convective storms are analyzed from records from dense networks of recording rain gages in four study areas in Arizona and New Mexico. The primary study areas are the 58-square-mile Walnut Gulch Experimental Watershed at Tombstone, Arizona, and the 67-squaremile Alamogordo Creek Watershed near Santa Rosa, New Mexico. Three “record” storms of differing character occurring in 1960 and 1961 on Alamogordo Creek Watershed and one “record” storm in 1961 on the Wlanut Gulch Watershed are analyzed and compared in detail.  相似文献   

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SUMMARY

Basing their studies on an extended Reynolds principle of similarity, the authors present in this paper a thorough theoretical investigation of the turbulent flow in pipes.

Making appropriate assumptions regarding the distribution of the turbulent apparent viscosity over the entire pipe diameter, the well-known discharge formulas, i. e. the resistance laws, of Prandtl-V. Kármán for the hydraulically smooth and the hydraulically rough region, and of Colebrook for the transition region—the accuracy of these being well established by measurements—can be clearly shown to be correct.

Thus it is also possible to determine the velocity distribution in the region near the wall for the hydraulically smooth region and the transition region, as well as for the hydraulically rough region.

The concept, that the flow with a fully developed roughness effect begins when the laminar boundary layer at the wall disappears can be seen to be in close agreement with the asssumptions made. The limits which were established for the hydraulically rough region and the transition region correspond well with the curve plotted by PRANDTL and the boundary curve of Rouse.  相似文献   

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Abstract

A simple method is used to study the response of runoff in the Sahel to climate change. The statistical characteristics of rainfall are calculated over the western part of the Sahel for the period 1961–1990, using the BADOPLU network. Daily rainfall is simulated using a Markov process with Weibull distribution for rainfall depths. Runoff is modelled using a conceptual SCS model and the curve numbers are calculated for West Africa. Climate change is provided by simulations using the Arpège GCM (Scenario A1B), and a perturbation method is used on the parameters which describe the rainfall. Changes in rainfall are assumed to occur through increases in frequency, not intensity. Using Arpège, runoff is mainly found to increase, in depth and in number of events, by the end of the 21st century. Changes in evaporation and land use are not included in the analysis. The impact of this 21st century potential climate change (rainfall) on the runoff is found to be of the same magnitude as the impact of changes in land use.  相似文献   

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