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In the article the author looks back the hard development course and great progress in earth quake science and technology in China during the last near a half of century and expounds the following 3 aspects: (1) The strong desire of the whole society to mitigate seismic disasters and reduce the effect of earthquakes on social-economic live is a great driving force to push forward the development of earthquake science and technology in China; (2) To better ensure people‘ s life and property, sustainable economic development, and social stability is an essential purpose to drive the development of earthquake science and technology in China; and (3) To insist on the dialectical connection of setup of technical system for seismic monitoring with the scientific research of earthquakes and to better handle the relation between crucial task, current scientif ic level, and the feasibility are the important principles to advance the earthquake science and technology in China. Some success and many setbacks in earthquake disaster mitigation consistently enrich our knowledge regarding the complexity of the conditions for earthquake occurrence and the process of earthquake preparation, promote the reconstruction and modernization of technical system for earthquake monitoring, and deepen the scientific research of earthquakes. During the last 5 years, the improvement and modernization of technical system for earthquake monitoring have clearly provided the technical support to study and practice of earthquake prediction and pre caution, give prominence to key problems and broaden the field of scientific research of earth quakes. These have enabled us to get some new recognition of the conditions for earthquake oc currence and process of earthquake preparation, characteristics of seismic disaster, and mecha nism for earthquake generation in China‘s continent. The progress we have made not only en courages us to enhance the effectiveness of earthquake disaster mitigation, but also provides a basis for accelerating further development of earthquake science and technology in China in the new century, especially in the 10th five-year plan. Based on the history reviewed, the author sets forth a general requirement for develop ment of earthquake science and technology in China and brings out 10 aspects to be stressed and strengthened at present and in the future. These are: upgrade and setup of the network of digitized seismic observation; upgrade and setup of the network for observation of seismic pre cursors; setup of the network for observation of strong motion; setup of the laboratories for ex periment on seismic regime; establishment of technical system for seismic information, emer gency command and urgent rescue; research on short-term and imminent earthquake predic tion; research on intermediate- and long-term earthquake prediction; research on attenuation of seismic ground motion, mechanism for seismic disaster, and control on seismic disaster; ba sic research fields related to seismology and geoscience. We expect that these efforts will signifi cantly elevate the level of earthquake science and technology in China to the advanced interna tional level, improve theories, techniques, and methods for earthquake precaution and predic tion, and enhance the effectiveness of earthquake disaster mitigation.  相似文献   

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(黄培华)(苏维加)(陈金波)SeismicityandstressfieldinOkinawaTroughandRyukyuregions¥Pei-HuaHUANG;Wei-jiaSUandJin-BoCHEN(DepartmentofEartha...  相似文献   

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Crustal movement and deformation in Taiwan and its coastal area   总被引:1,自引:0,他引:1  
Introduction Both Taiwan Island and Chinese mainland belong to Eurasian plate in geological structure. And the nearest distance between Taiwan Island and Fujian Province, which is located on the opposite coast, is only 130 km. Although there are high-precision GPS networks in both Taiwan and Fujian Province, joint GPS measurement cannot be made directly because of the inconvenient contact due to the strait between them. However, the GPS networks arranged on b…  相似文献   

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INTRODUCTIONItisknownthatChinaisanearthquake pronecountryintheworldandisalsoacountrysufferingmostsevereseismiccalamitiesintheworld .China’sterritoryoccupiesabout 1 1 4oftheglobalconti nentalarea ,whileabout 1 3ofglobalM≥ 7.0continentalearthquakesoccurredinCh…  相似文献   

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Introduction Hilbert-Huang transform (HHT) is a great break in processing nonlinear and non-stationary data and can be successfully used in many science domains. There are mainly two parts in this method. The first part is to decompose the original data into several intrinsic mode functions (IMF) with the empirical mode decomposition (EMD). IMF components are derived from the original data directly according to the local characteristics in the data under some rules, so that IMF are poste…  相似文献   

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Warming in the Arctic Intermediate Water (AIW) has been reported in a series of articles in recent years. Prior to 1992, the water temperature of AIW off the Chukchi Continental Slope had never exceeded 0.5℃. Aagaard et al.[1] and Carmack[2] were the first to report that the temperature in AIW in the area in 1993 was close to 1℃, based on the data observed in a Canadian expedition. In 1994, the temperature of AIW around the Chukchi Sea and Mendeleyev Ridge again rose by at least an…  相似文献   

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Introduction Rayleigh wave is a kind of seismic wave propagating along the surface of the Earth, its propagation speed depends chiefly on the S-wave velocity structure of the Earth. Rayleigh wave energy of different periods concentrated in different depth ranges. The layered structure of the Earth causes the phenomenon of dispersion of surface waves, that is, surface waves of different periods are propagated with different speeds. By measuring the dispersion curves of surface waves the S-wav…  相似文献   

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Vegetation and soil carbon storage in China   总被引:18,自引:2,他引:18  
This study estimated the current vegetation and soil carbon storage in China using a biogeochemical model driven with climate, soil and vegetation data at 0.5° latitude-longitude grid spatial resolution. The results indicate that the total carbon storage in China's vegetation and soils was 13.33 Gt C and 82.65 Gt C respectively, about 3% and 4% of the global total. The nationally mean vegetation and soil carbon densities were 1.47 kg C/m2 and 9.17 kg C/m2, respectively, differing greatly in various regions affected by climate, vegetation, and soil types. They were generally higher in the warm and wet Southeast China and Southwest China than in the arid Northwest China; whereas vegetation carbon density was the highest in the warm Southeast China and Southwest China, soil carbon density was the highest in the cold Northeast China and southeastern fringe of the Qinghai-Tibetan Plateau. These spatial patterns are clearly correlated with variations in the climate that regulates plant growth and soil organi  相似文献   

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By analyzing the gravity,magnetic,seismic and drilling data,the authors in this paper calculate and construct the density structure of the crust and upper mantle along the Haoding-Chengde and Zhangjiakou-Tanggu profiles and residual gravity anomalies in the region.The compiled residual gravity anomalies g2 and g4 maps reflect qualitatively the spatial distribution of the density structure of the crustal "seismogenic layer" and the uppermost mantle layer at depth of 50-75 km in the region.In order to reveal the relationship between density structure and seismicity,a great number of statistic calculations and comparisons of the available data and the results indicate that the seismicity in the crustal "seismogenic layer" is characterized by block movement:moderate-small earthquakes occurred generally within the blocks,moderate-strong earthquakes mostly along the borders of the blocks,strong earthquakes mostly at the edges and corners of the blocks.And aftershocks of strong earthquakes tended to occur at o  相似文献   

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Geology and Exploration of Oil and Gas in the Ordos Basin   总被引:2,自引:0,他引:2  
The Ordos basin is rich in oil and gas resources. The structures in the basin are generally rather gentle. Most of the oil and gas pools already found are belong to the types of lithologic, lithostratigraphic and paleo-geomorphic with thin reservoirs. The geology of oil and gas and the generation and distribution of oil and gas resources in the Ordos basin is analyzed in detail in the paper. It is also pointed out in the paper that what direction should be taken in oil and gas exploration in the basin, and that the important role of the seismic prospecting technologies in the discovery of large oil and gas fields in the basin could not be replaced.  相似文献   

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210Po and 210Pb in mussel (Mytilus galloprovincialis) and sediment samples collected at Candarl? Gulf during the period of 2010–2012 are presented and discussed. The activity concentrations of 210Po and 210Pb were measured by means of alpha spectrometry. Activity concentrations of 210Po and 210Pb in mussels are in the ranged of 332 ± 17–776 ± 23 Bq kg−1 dw and 14 ± 1–40 ± 5 Bq kg−1 dw, for sediments the ranges for 52 ± 5–109 ± 8 Bq kg−1 dw and 38 ± 5–92 ± 9 Bq kg−1 dw, respectively. The estimated consequent annual effective ingestion dose due to 210Po and 210Pb from mussel consumption in Candarl? Gulf coastal region were calculated. The highest dose due to 210Po and 210Po were calculated to be 4232 ± 126 μSv and 126 ± 16 μSv, respectively.  相似文献   

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The temporal variation of LURR(y)for Kanto,Wakayama,and Hugo regions in Japan has been calculated and analysed.The LURR(y)values are significantly higher than 1 before the occurrence of all earthquakes with magnitude M≥6.0 in the Kanto region during the last two decades and the Kobe earthquake(1995-01-17).These results suggest that LURR theory is available for Japan.Recently they-value for Wakayama region has been near 1,while the y-value is remarkably larger than 1 for nearly two years for Kanto.According to these results,it is predicted that a strong earthquake with magnitude of about 6.0 could occur in 1 year or a little longer for in Kanto region or its adjacent regions,but there is little possibility for the Wakayama region.  相似文献   

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SynthesizedPoissonandrenewalmodelanditsapplicationinseismichazardanalysisHan-YaoCHEN(陈汉尧)andYu-XianHU(胡聿贤)(InstituteofGeophys...  相似文献   

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Monthly data of Self-Calibrated Palmer Drought Severity Index (PDSI) from 1951 to 2000 are calculated using historical precipitation and temperature data for Chinese 160 stations. Temporal and spatial pat-terns of the first empirical orthogonal function (EOF) of the PDSI reveals a fairly linear trend resulting from trends in precipitation and surface temperature, which is similar to the linear PDSI trend during 1951―2000 calculated using all monthly data. The EOF analysis also reveals that the leading mode correlates significantly with ENSO events in time and space. The ENSO EOF shows that during the typical warm phase of ENSO, surface conditions are drier in most regions of China, especially North China, but wetter than normal in the southern regions of Changjiang River, and Northwest China. During the typical cold phase of ENSO, these anomalies reverse sign. From 1951 to 2000, there are large multi-year to decadal variations in droughts and wet spells over China, which are all closely related to strong El Nio events. In other words, when one strong El Nio event happens, there is a possible big variability in droughts and wet spells over China on the multi-year or decadal scale. Studies also sug-gest that during the last 2―3 decades climate changes over China, especially North China's drying and northwest China's wetting, are closely related to the shift in ENSO towards warmer events and global warming since the late 1970s. The instability of the relationship is also studied. It is revealed that there is a good correlation between ENSO and Chinese variations in droughts and wet spells in the 3―8-year band, but the correlation between ENSO and Chinese variations in droughts and wet spells is instable. Studies suggest that there are decadal changes in the correlation: the wavelet coherency between ENSO and Chinese variations in droughts and wet spells is high during 1951―1962 and 1976―1991, but low during 1963―1975 and 1992―2000.  相似文献   

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Introduction The Chinese mainland is located in the southeastern part of Eurasia plate and encircled by India, Eurasia, Pacific and Philippine Sea plates. It is one of areas with the strongest tectonic de-formation, especially Qingzang (QinghaiXizang) plateau and NS tectonic zone where the tec-tonic activity is more intensive and intricate. The main part of tectonic activity of Chinese mainland includes a series of tectonic zones and active blocks divided by them. Therefore, the research…  相似文献   

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Zedník  J.  Pospíšil  J.  Růžek  B.  Horálek  J.  Boušková  A.  Jedlička  P.  Skácelová  Z.  Nehybka  V.  Holub  K.  Rušajová  J. 《Studia Geophysica et Geodaetica》2001,45(3):267-282
In the time span from January 1995 to December 1999 the Czech National Seismological Network (CNSN), consisting of ten permanent digital broadband stations, several local networks and two data centers, detected and recorded 9530 regional natural seismic events, 27 greater than magnitude 2. Most of these events were located by the Czech Seismological Service (CSS), and the most prominent of them were analyzed in detail. A large number of quarry blasts were recorded as well but were not included in the analysis. We provide basic information on the configuration of the CNSN and on the way of routine data processing employed by the CSS in this paper. The over-all regional seismicity monitored by the CNSN in 1995–1999 is briefly reviewed. The main results of observations and evaluation of the local (NW-Bohemia/Vogtland, South Bohemia, Sudeten) and induced (Kladno, Píbram, Upper Silesia, Lubin/Poland) seismic activity within this period are presented in a condensed form. Finally, a summary on macroseismic observations on the territory of the Czech Republic in 1995–1999 is also presented.  相似文献   

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《水文科学杂志》2013,58(4):781-792
Abstract

Groundwaters of known age contained in major aquifer systems in the African sedimentary basins enable low-resolution (±1000 year) characteristics of past climates to be determined, specifically palaeo-temperature, air mass origins, humid/arid transitions and rainfall intensity. Results from both northern and southern Africa indicate the predominance of a westerly Atlantic air flow during the Late Pleistocene. Greater aridity during the Last Glacial Maximum (LGM) is recorded over most of northern Africa by the absence of dated groundwaters. An intensification of the African monsoon during the Early Holocene is apparent from isotopically light groundwaters found, in particular, over Sudan. Maximum cooling around the LGM of 5–7°C is recorded in the noble gas recharge temperatures from Africa. Modern recharge can be readily identified from the chemical and isotopic signatures (Cl, δ18O and 3H) in the unsaturated zone and in shallow groundwaters. The results indicate the non-renewability of many groundwater sources now being exploited across the arid and semi-arid regions of Africa. Extreme events in the past, noted from the groundwater record, may have lessons and implications for adapting to future climate change. Small but finite amounts of renewable groundwater may be estimated using chloride mass balance and other tracer techniques. These renewable waters form the basis of sustainable development in areas such as the Sahel. Based on the field evidence of water scarcity, new approaches are needed in management and education to adapt to the current limited resources in the face of changing climates.  相似文献   

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