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总结回顾了江苏二十多年来的防震减灾工作,分析了当前搞好防震减灾工作的形势,从7个方面阐述了要抓住机遇,依法行政提高全省防震减灾工作水平的有关问题。  相似文献   

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梅岭,又名大庾岭,为南岭山系五岭之首。梅关是粤赣交界的险关要塞,素有“岭南第一关”之誉,秦汉以前已存在。梅岭以梅花著称。古道与关同时出现,到唐初张九龄扩展岭路成坦途。  相似文献   

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Thefaultplaneofthe1991,Datong-Yang-gao,Shanxi,China,Ms=5.8earthquakeMingWANG(王鸣),Lian-QiangZHANG(张廉强)andPei-DeWANG(王培德)(Insti...  相似文献   

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Introduction The June 4, 2000 southern Sumatra, Indonesia, earthquake (16h28min26.2s UTC, 4.72, 102.09, 33 km, MS=8.0 [IRIS]) occurred under the Indian Ocean, near the Mentawai fault, along the well-known Sumatran subduction zone and the great Sumatran fault, all of which trend northwest-southeast. 1 800 houses were totally destroyed, 10 196 were heavily damaged, and 18 378 were slightly damaged by the earthquake. At least 97 people were killed, 1 900 were injured, and 122 000 were left…  相似文献   

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《Astronomy& Geophysics》2009,50(2):2.10-2.11
Professional astronomy operates in a world of big-budget, complex instruments, competition for observing time, and publishing deadlines. Sue Bowler asks how amateur astronomers fit into this world – if at all.  相似文献   

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多种岩石的Qp,Qs,Qc   总被引:2,自引:0,他引:2  
许昭永  段永康 《地震研究》1996,19(2):192-198
本采用脉冲传播谱振幅比法、能量法、尾波法分别测多种岩样的P波Q值、S波Q值及尾波Q值。结果表明,能量法所得Qp、Qs较小。谱振幅比法所得Qp一般居中,Qs较大。尾波Qc有的偏大,有的偏小。  相似文献   

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Selecting three half orbits near the epicenter of Pu'er earthquake, we analyzed the Ne data recorded in their revis-ited orbits during a year before this earthquake, and extracted Ne precursors. The results show that: ① There are significant seasonal variations of ionospheric Ne in night time, which exhibit different shapes respectively in four seasons; ② There are three main shapes of Ne: single-peak, saddle-shaped and even-shaped, all of which may oc-cur in four seasons, but each season with its typical s...  相似文献   

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Selecting three half orbits near the epicenter of Pu’er earthquake, we analyzed the Ne data recorded in their revis-ited orbits during a year before this earthquake, and extracted Ne precursors. The results show that: ① There are significant seasonal variations of ionospheric Ne in night time, which exhibit different shapes respectively in four seasons; ② There are three main shapes of Ne: single-peak, saddle-shaped and even-shaped, all of which may oc-cur in four seasons, but each season with its typical shape relatively; ③ Spatial images of Ne showed high values near the epicenter in 30 days before the earthquake, and there is a good correlation between anomaly and distribu-tion of earthquake in space and time, which reflects that these spatial anomalies were indeed concerned with the earthquake; ④There shows a certain similarity of the Ne curves among revisited orbits, which can provide back-ground information for distinguishing and identification of seismic anomaly.  相似文献   

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Biogeomorphology has been expanding as a discipline, due to increased recognition of the role that biology can play in geomorphic processes, as well as due to our increasing capacity to measure and quantify feedback between biological and geomorphological systems. Here, we provide an overview of the growth and status of biogeomorphology. This overview also provides the context for introducing this special issue on biogeomorphology, and specifically examines the thematic domains of biogeomorphological research, methods used, open questions and conundrums, problems encountered, future research directions, and practical applications in management and policy (e.g. nature-based solutions). We find that whilst biogeomorphological studies have a long history, there remain many new and surprising biogeomorphic processes and feedbacks that are only now being identified and quantified. Based on the current state of knowledge, we suggest that linking ecological and geomorphic processes across different spatio-temporal scales emerges as the main research challenge in biogeomorphology, as well as the translation of biogeomorphic knowledge into management approaches to environmental systems. We recommend that future biogeomorphic studies should help to contextualize environmental feedbacks by including the spatio-temporal scales relevant to the organism(s) under investigation, using knowledge of their ecology and size (or metabolic rate). Furthermore, in order to sufficiently understand the ‘engineering’ capacity of organisms, we recommend studying at least the time period bounded by two disturbance events, and recommend to also investigate the geomorphic work done during disturbance events, in order to put estimates of engineering capacity of biota into a wider perspective. Finally, the future seems bright, as increasingly inter-disciplinary and longer-term monitoring are coming to fruition, and we can expect important advances in process understanding across scales and better-informed modelling efforts. © 2020 The Authors. Earth Surface Processes and Landforms published by John Wiley & Sons Ltd  相似文献   

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The earthquake catalog with the minimum completeness magnitude of ML=1.7 during the period from 1970 to 1976 has been used as basic data for the research on seismic quiescence in source area before occurrence of the July 1976 great Tangshan earthquake in China,based on the analyses of the detectability of seismic network,and of relation between earthquake magnitude and frequency in Northern China.The temporal processes of seismicity rate(January 1970-July 1976)before the July 1976 great Tangshan earthquake for four researched sub regions in and around source area(aftershock area)of the mainshock are investigated and compared.It is found that there exist abnormal seismic quiescence with duration of 38 months in the subregion located in western part of aftershock area,which is significant statistically at confidence level of 0.99 and larger by beta-test.In addition,because there were no false alarms except for the above abnormal interval in the west aftershock area,and the Tangshan mainshock and 85% of af  相似文献   

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Donald V.Helmberger was an unparalleled observa-tional seismologist,and theoretician.His pioneering work in seismic waveform modeling,and the numerical methods ...  相似文献   

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Introduction An earthquake of MS=7.8 occurred near the Gujarat of India on January 26, 2001, which was one of the most deadly earthquakes since there was the record in the Indian history (Bendick, et al, 2001; Gupta, et al, 2001). The USGS of USA determined the origin time of the earthquake to be 3h16min41s (UTC), and the epicenter location to be 70.32篍, 23.40篘. Shortly after the earthquake, the moment tensor solutions or focal mechanisms and other related parameters were offered by s…  相似文献   

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A recently discovered Bison-bearing fossil locality at Térapa, Sonora, Mexico, had previously been dated to 440 ± 130 ka using whole rock 40Ar/39Ar on a basalt flow that impounds the deposit. This age is considerably older than the accepted age of about 240–160 ka for the migration of Bison into greater North America. The Térapa deposit also contains a mixture of fossils from extralimital or extinct tropical animals and temperate animals. Constraining the age of the deposit is critical to interpret the paleontologic and paleoclimatologic implications of this unique Sonoran fossil locality. Three additional geochronological methods have been applied to this deposit (infrared stimulated luminescence (IRSL), amino acid racemization (AAR), and radiocarbon) and the data from the original 40Ar/39Ar age were revisited. The IRSL data suggest that the impounding basalt flow and the sediments that abut it were emplaced 43 ka ago and that the oldest sediments were deposited shortly after. Two radiocarbon ages suggest the fossiliferous sediments were emplaced by 42 ka. Effective diagenetic temperatures inferred from the AAR results, combined with AAR data from a similar-age deposit in southern Arizona, are in accordance with the 40–43 ka age estimates. For the AAR results to corroborate the 40Ar/39Ar age, the effective diagenetic temperature for the area would need to be approximately 3 °C, which is unrealistically low for northern Mexico. The new geochronological results suggest the Térapa deposit and fossils are 40–43 ka old. The anomalously old 40Ar/39Ar age for the impounding basalt is probably the result of low 40Ar* concentrations and inherited 40Ar.  相似文献   

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