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101.
城市群地震灾害特点与防震减灾对策 总被引:7,自引:0,他引:7
城市群是我国经济迅速发展的产物。我国东部地区已经涌现了大量的城市群。城市群地震灾害比单个城市的地震灾害更为复杂、严重。地震对社会经济的影响更大。本文首次对城市群的地震灾害特点、防震减灾对策进行了系统的讨论,并着重指出了城市群防震减灾研究的重点领域。 相似文献
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1 INTRODUCTION Dongting Lake lies south of the middle reach of the Yangtze River in Hunan and Hubei provinces (Fig. 1). On the north side of Dongting Lake, there are the three diversion openings of the Yangtze River named Songzi, Taiping, and Ouchi, and, on the south and west sides, there are the four tributary streams named Xiang, Zi, Yuan, and Li Rivers. The flow of the three diversion openings and the four tributary streams runs into Dongting Lake, and runs out at Chenglingji a… 相似文献
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In this paper, we briefly describe the general destruction caused by historic earthquakes in major cities of China, preliminarily analyze the heaviness and widespread occurrence of earthquakes in cities of China, and suggest that research on scenario earthquakes in cities should be developed as a part urban disaster reduction research. 相似文献
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渭干河流域"2002·7"特大洪水分析 总被引:6,自引:0,他引:6
渭干河是塔里木河流域第六大源流, 位于天山西部南麓, 渭干河干流起点有新疆最大的流域性控制工程--克孜尔水库. 2002年7月下旬天山中西部山区出现大暴雨(雪)过程, 渭干河流域山区降水持续时间长达30 h以上, 山区降水量50 mm左右, 导致5条支流和渭干河干流出现有水文记录以来的最大洪峰, 流量超过警戒流量和危险流量的2~3.5倍, 暴雨(雪)过程结束之后, 融雪型洪峰长时间居高不下. 洪水过程中, 各支流以及暴雨与融雪等多种洪峰遭遇现象很明显. 克孜尔水库入库洪峰流量达3 660 m3*s-1, 经水库调洪错峰, 出库峰值流量为1 000 m3*s-1, 削峰率72.7%. 相似文献
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Abstract A controversial stratigraphic section, the Taneichi Formation, is exposed along the Pacific Coast of northeastern Honshu, the main island of the Japanese Archipelago. Although most sediments of the formation have long been dated as late Cretaceous, the northern section of it has been assigned to (i) the Upper Cretaceous; (ii) the Paleogene; or (iii) the Neogene. In the present report, we present the data of palynological and sedimentological studies, showing that the northern section should be assigned to the Neogene. A more important point in the present study is that we invoke some basic principles of fluvial sedimentology to resolve this stratigraphic subject. The lignite layers full of Paleogene–Miocene dinoflagellate cysts and pollen assemblages drape over the boulder‐sized (>40 cm in diameter) clasts in the northern section. However, the layers totally consist of aggregates of small lignite chips, indicating that the lignites are allochthonous materials. The mega‐clasts with derived microfossils in the lignites are thought to have been deposited as Neogene fluvial (flood) sediments in the newly formed Japanese Archipelago. Prior to the Miocene, the northern Honshu was part of the Eurasian Plate, thus the boulder‐sized clasts cannot be envisaged as long river flood deposits along the continental Paleogene Pacific Coast. Instead, the mega‐clasts with the draping lignites were probably derived from nearby Miocene highlands in the newly born island arc. 相似文献
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Preliminary Rock-Slope-Susceptibility Assessment Using GIS and the SMR Classification 总被引:1,自引:1,他引:1
This paper aims to examine the impact of large-scale structuraladjustments (like the Greater Dhaka Flood Protection Project, GDFPP) on local living environment.It focuses the importance of environmental factors in flood hazard mitigation, and examines theenvironmental attitudes of the floodplain residents arising from the large-scale structural adjustments.Based on `perceived natural hazard research perspectives', this paper examines: (i) the reasons for persistentfloodplain occupation, and (ii) the importance of environmental factors in the choice, motivations and decision-makingof floodplain residents.This research used data collected from 300 households situated inthe eastern part of Dhaka. The face-to-face household survey data provided individuals' responses to a structuredquestionnaire on hazards and environment. Survey concerned urban floodplains, and looked fordata on housing, household characteristics, and residents' attitudes. Results of interview surveys wereused to: (i) explore the reasons of floodplain occupation, and (ii) residents' attitudes to tolerable levelof flood risk and willingness to accept environmental change resulting from the proposed structural embankments inthe eastern perimeter of Dhaka City, Bangladesh.Findings revealed that floodplain occupation (by theindividuals' decision-making) was a result of overall reaction to the Government's structuraladjustment policies that resulted from institutional, locational and socio-economic factors. The attitude survey results provided residents' perception to hazards and environment to be dependenton the socio-economic factors – but in a complex manner, many factors are interrelated.In addition to support for structural embankments, the study sample displayed a common concernand widespread environmental awareness. In terms of any `trade-off' between thebenefits (resources) from the embankments and costs (hazards) due to the detrimental impact on environment, the residents of Dhaka, despite some concern forsacrificing embankments for environment, tended to show a generalconsensus for embankments. 相似文献