Table of Content

08 September 2005, Volume 27 Issue 3

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Brief Report

ON THE ACTIVITY OF THE TOUPO FAULT IN THE SOUTHERN ANHUI PROVINCE

CHEN Wen-bin, LI Xiao-jun, SONG Yi-sheng, PAN Hua, HUAN Wen-lin, XU Guang-yin, JIANG Hui, YOU Hui-chuan

2005, 27(3):  353-360. 

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The Toupo Fault,located in the southern Anhui Province,strikes N60°～70°E in a linear route that is clear on satellite image. It plays an important role in controlling the tectonics,topography and distribution of Mesozoic-Cenozoic basins and strata. Detailed field investigation was carried out along the Toupo Fault about its activity. Profiles as well as a trench excavated reveal that the Quaternary superstratum above the fault has not been offset. The stratum was sampled and dated with TL methods to be the Mid-Pleistocene time,implying that the fault has been no longer active since then. Three stages can be divided since the fault was formed,namely,the first stage (late Yanshan Movement),when the fault movement was of reversal left-lateral strike-slipping and the tracks formed then are still clear today; the second stage (early Himalayan Movement-the late Cretaceous-early Tertiary),when the fault movement turned to be normal faulting and the southern wall became a tensile basin and received clastic sediments; and the third stage (since the late Tertiary),when the tectonic movement was very week. No late Tertiary sediments were formed and the Quaternary sediment is only as thick as tens meters. The topography also suggests an old-age form. Neither vertical nor horizontal displacement was evident along Toupo Fault during this stage,though fault gouge dating suggests the Toupo Fault might have been active during the Middle Pleistocene.

THE THRUST ACTIVITY OF THE ALTYN FAULT ZONE SINCE THE MIDDLE AND LATE PLEISTOCENE

ZHENG Rong-zhang, XU Xi-wei, WANG Feng, LI Jian-ping, JI Feng-ju

2005, 27(3):  361-373. 

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Among the Altun Tectonic system,there are thrust faults and thrusting components in the Altun strike-slip fault zone. Being similar to the Altun strike-slip fault zone,the thrust fault can be divided into three segments. They are the western segment,middle segment and eastern segment. The western segment is from Ayinaike to the debouchment of the Cheerchenhe River. There is thrusting component on the southern marginal fault of Altun and there are small thrust faults in piedmont in the western segment and evidences are discovered that show the latest terraces and alluvial fan being affected by thrust activity. The middle segment is from the debouchment of Cheerchenhe River to Lapeiquan. There are large-scale thrust faults in the northern margin of Altun Mountains,and there is evidence to show the younger surface of landform displaced by the thrust activity of the middle segment. The eastern segment is from Lapeiquan to Kuantanshan. There is thrusting component on the northern marginal fault of Altun,and thrust faults are developed on the northern margin of Altun Mountains and pediment alluvial fan. From the middle and late Pleistocene to present,the thrust rate on the middle and eastern segments of thrust fault is less than 2mm/a. Since 16ka BP,the thrust rate in Jianggalasayi on the west of the middle segment is 0.33mm/ a,the thrust rate in Milanqiao on the middle part of fault is 1.42mm/a since 32ka BP. The thrust rate of the middle part is bigger than that of the western part. The biggest thrust rate of the eastern segment is at Tuanjiexiang near to the middle part,being 1.81mm/a. From the middle part to the eastern or western part,the thrust rate becomes smaller. At Liuchengzi of the western part,the thrust rate is 0.57mm/a since 72.36ka BP. While at Hongliugou of the eastern part,the thrust rate is only 0.05mm/a since 8.99ka BP.

RESEARCH ON THE SATELLITE REMOTE SENSING IMAGES INDICATIVE OF STRONG EARTHQUAKE PREPARATION IN THE ORDOS NORTH MARGINAL FAULT BASIN REGION

LI Jian-hua

2005, 27(3):  374-381. 

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The information of tectonic movement in the earthquake-stricken areas of the 1979 M_S 6.0 Wuyuan earthquake,the 1989 M_S 6.1 Datong-Yanggao earthquake and the 1996 M_S 6.4 west Baotou earthquake are studied by using multi-phase and multi-channel satellite images. Furthermore,the geologic-tectonic background of these earthquakes is discussed by combining the obtained results with the existing seismic intensity investigation data. The results of this study show that the 1979 M_S 6.0 Wuyuan earthquake occurred at the convergence of the NE-trending Haiziyan Fault and the NW-trending west Wuyuan Fault,as indicated by tone difference and micro-morphologic features on satellite images. The long axis of the high intensity isoseism of this earthquake is NE-trending,consistent with the Haiziyan Fault,which is therefore assumed to be the seismogenic fault of this earthquake. The long axis of the low intensity isoseism of this earthquake is NW-trending,indicating the effect of the NW-trending west Wuyuan Fault. The 1989 M_S 6.1 Datong-Yanggao earthquake occurred on the NEE-trending Dawangcun-Xi'anquan Fault which extends from the hinterland of the Liulengshan Mountains to Datong-Yanggao basin,as indicated by micro-morphologic and tone differences on the satellite images. The fault is consistent with the long axis of the isoseism of this earthquake as proposed by Su Zong-zheng et al. The 1996 M_S 6.4 west Baotou earthquake occurred at the convergence of the Wulashan north marginal fault and the NW-trending Xinsheng Sand Yard Fault,as indicated by distinct scarp and groove landforms. The long axis of high intensity isoseism of this earthquake is NE-striking,sub-parallel to the NEE-trending Wulashan north marginal fault that is assumed to be the seismogenic structure of the west Baotou earthquake. The long axis of low intensity isoseism of this earthquake is NW-striking,which is considered to be the effect of the NW-trending Xinsheng Sand Yard Fault.

THE PRELIMINARY STUDY ON MACRO-SCALE ZONATION OF EARTHQUAKE EMERGENCY RESPONSE (EER) OF CHINA

SU Gui-wu, DENG Yan, NIE Gao-zhong

2005, 27(3):  382-395. 

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The factors,that have impacts on earthquake emergency response (EER) in a region,mainly involve the following three aspects,the seismic activities,the physical geographic environments and the social-economic conditions. In different regions,the overall seismic activity levels and features at various time scales are the basic reference for constructing the EER system at ordinary times and making emergency response preparedness when earthquake is impending. The physical geographic environments of each region determine the distinct emergency response and relief background and surroundings of various regions at the macro and holistic level,and the disaster-formation processes and patterns of an earthquakes occurring in different physical geographic environments usually have marked region-specific characteristics,so the EER will be more efficient when these regional processes and patterns are dealt with properly. For a certain intense earthquake,the social-economic conditions are the determinant factors in defining what forms and how serious the earthquake disaster will be,and thus affecting EER directly and evidently. At the same time,the different social-economic conditions of different areas also mean the different transportation and communication,medical and rescue facilities,relief resources,as well as self- and mutual relief competences. All these three aspects interweave together and make the EER issue be branded of inevitably remarkable regional or local-specific natures. Based on the above cognition,we take the regional integrated seismic risk,the population-economy density,earthquake-induced secondary natural hazards,local EER input potential coefficient and the local high-rank road density as zonation criteria or indexes,to carry out the macro-scale zonation of EER of Chinese mainland using the principal factor method,overlay method and geographical correlation analysis and through the top-to-bottom region-dividing process. The result shows that the Chinese mainland can be divided into eight macro-scale EER regions,namely,the Northeast China-eastern Inner Mongolia EER region (Ⅰ),the North China EER region(Ⅱ),the Southeast China EER region(Ⅲ),the Loess Plateau EER region(Ⅳ),the Guizhou Plateau-eastern Sichuan EER region (Ⅴ),the Yunnan-western Sichuan EER region(Ⅵ),the Xinjiang EER region (Ⅶ) and the Qinghai-Tibetan Plateau EER region(Ⅷ). The result also suggests that the macro-characteristics of EER in each region are different markedly and they shall be taken as the primary reference basis for planning,implementing and developing the region-specific EER countermeasure systems in the respective regions.

DEVELOPMENT OF EARTHQUAKE DAMAGE EVALUATION AND DAMAGE DATA MANAGEMENT SYSTEM (EDMS) ——A CASE STUDY ON LIJIANG EARTHQUAKE DAMAGE

HE Hong-lin, SONG Xin-chu

2005, 27(3):  396-411. 

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Once an earthquake occurs,the rapid and reliable evaluation of earthquake damages will be of great importance to the mitigation of earthquake hazards and the reconstruction of the disaster area. In recent years,a lot of work has been done in the development of GIS-based systems for improving and accelerating the evaluation of earthquake damage,but such systems were mostly developed for the urban region in developed countries. Therefore,we developed an “Earthquake Damage Evaluation and Damage Data Management System (EDMS)” for the rural regions in the southwestern China on the guidance of the “Working Regulation and Technical Guideline for Earthquake Field Investigation” issued by China Earthquake Administration in 1998. This system provides elementarily visualized tools for evaluating earthquake damage and managing damage data. The mapping and interpolation functions of GIS developed in the EDMS system have also facilitated the analyses of earthquake damage and seismic intensity as they are more accurate than the previous ones. The analysis of Lijiang earthquake of 1996 by using this system has revealed that the seismic intensity of this event does not decrease simply with the increase of distance to the epicenter,but displays a complex distribution pattern. This complexity can be attributed to the thick alluvium in the basins and the structure of fault systems in the region. Although it is an incomplete system just suitable for rural regions in southwestern China,the EDMS system is expected to be applicable to the evaluation of earthquake damage in broad rural regions of China,and it may be helpful to raising the ability of earthquake damage mitigation in China.

NUMERICAL SIMULATION OF COMPLEX RESISTIVITY WELL LOGGING IN DUAL LATEROLOG MODE

YANG Wei

2005, 27(3):  412-419. 

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Complex resistivity well logging (CRWL) is a new well logging method for differentiating and evaluating the saturation of rock formation through its frequency dispersion character. The current tool used in the field is actually the modified dual laterolog tool. The tool can be used to measure deep and shallow laterologs at two different frequencies. The ratio of low frequency (0～200Hz) to high frequency (1～20k) is used to evaluate the formation. The bigger ratio means the higher oil saturation. CRWL has been used in some oil fields for several years and a lot of data has been collected. However,some eata are vague and need to be clarified through more theoretical studies. In this paper,we start from Maxwell equation for electromagnetic field.Considering the boundary condition and specific well logging environment,we deduce Maxwell equation into a boundary value of Laplace equation.Using the variational method,we get the variational formula to satisfy the finite element method. In 2D formation model,we use finite element method (FEM) to simulate the CRWL response at different frequencies working in DLL mode. The results show that the responses agree with DLL when the frequency is near zero,and the readings of response reduce when the frequency increases. When the formation has some extant frequency dispersion,the readings of different frequencies will disperse. Then,the readings of complex resistivity logs at different frequencies can be used to differentiate oil layer from the water layer. Also they can be used to evaluate the saturation of a formation.

GEOELECTRIC POTENTIAL ANOMALIES BEFORE EARTHQUAKES IN THE JOINT AREAS OF SHANXI, HEBEI AND INNER MONGOLIA

ZHANG Xue-min, GUO Xue-zeng, GUO Jian-fang

2005, 27(3):  420-428. 

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With the continuous observation of earth resistivity,there are more than 30 years'observation records of geoelectric potential in many stations,but analysis on them is relatively lacking. In this paper,we analyzed the variations of geoelectric potential before three earthquakes above 6.0 and one earthquake above 5.0,which are located at the joint areas of Shanxi Province,Hebei Province and Inner Mongolia Autonomous Region. Some similar features are found in these anomalies recorded at 5 stations in a distance of about 300km: (1)The majority of anomalies shows a step-variation type,which means rising quickly (or dropping quickly) at first,then turning to change slowly,and finally dropping quickly (or rising suddenly),and then the earthquake occurs. Sometimes it shows the type of quick turning from sudden rise or drop,and the earthquake occurs around the high point or the low point. (2)The anomalies have apparent imminent characteristic. In statistics,9 anomalies out of 10 presented themselves one month before earthquakes,and 7 anomalies just began to appear at one month before earthquake. (3)The anomalies have a lasting feature,which indicates that they will not end with the occurrence of earthquake,but continue for a period of time after the earthquake. They scarcely cease with earthquake occurrence. (4)Usually,anomaly only occurs at one measuring direction,on each station before strong earthquakes,and there is no synchronous variation on the other measuring directions. The anomalies in our study mainly appeared at northwest or east-west directions,which was related to the location of epicenters. (5) The amplitude of anomalies is correlated to the magnitude of earthquake and the epicentral distance. The bigger the magnitude is and the smaller the epicentral distance is,the relatively bigger amplitude of anomaly recorded by stations will be. Finally,compared with the groundwater table data,it is considered that this type of anomaly is related to the electrokinetic effect induced by movement of underground fluid to epicenter area during the earthquake preparation,when pore pressure of rocks is enlarged and fractures increased in epicentral areas under the action of regional stress field.

PRELIMINARY ANALYSIS OF KINEMATIC FEATURES OF A FAULT ZONE BY SEISMIC MOMENT TENSORS

LIU Chun, SHAO Hui-cheng, SHI Jun, KONG De-quan

2005, 27(3):  429-436. 

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In this paper,the method for inversing the kinematics parameters of a fault zone from seismic moment tensors is discussed and applied to the study of the present kinematics characteristics of Xianshuihe Fault zone and Fenwei Fault zone. The results show that the Xianshuihe Fault zone extends in the direction of N16癢 and is compressed in the direction of N74癊. The average sinistral motion rate is about 10.9 mm/a. The Fenwei Fault zone extends in N20癢 and is compressed in N78癢 direction. The average dextral motion rate is about 0.24mm/a. Comparing the results mentioned above to the geological information and the GPS results,it is found that the motion directions of fracture zone are basically agreeable,but the slip rate is less than that of the latter two,especially in the Fenwei Fault zone. Three reasons may explain this phenomenon,firstly,the time when the data are collected is different; secondly,all strain energy produced by geological body is assumed to be released by means of the stick slip,instead of creep-slip of the fault; and thirdly there were totally 14 earthquakes of magnitude greater that 5 occurring in the sampled time period,among which there was only one earthquake of maximum over 6 and the largest event is M 6.2. The motion rate of the fault zone calculated from seismic moment tensors is less than the average rate drawn by geological information. This shows that the strain energy of the geological body has not been released completely. So there exists high seismic risk. In addition,the motion rate of the Fenwei Fault zone is less than that of the Xianshuihe Fault zone,indicating that the level of seismicity and the energy released by earthquake of the former is less than that of the latter.

INVERSION OF Q VALUE, SITE RESPONSE AND SEISMIC SOURCE PARAMETERS IN FUJIAN AREA USING DATA OF DIGITAL SEISMIC STATION NETWORK

LI Zu-ning, ZHOU Zheng-rong, LIN Shu, CHEN Xiang-xiong, BAO Ting

2005, 27(3):  437-445. 

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Using the waveform data of M≥2.5 earthquakes from Fujian digital seismic station network since 1998,the inelastic attenuation coefficient,geometric diffusion coefficient,site response and seismic source parameters of seismic waves of Fujian area are calculated based on the algorithms proposed by Atkinson et al. Considering that the site response calculated by Atkinson's method is only the relative response,the method proposed by Moya is used to recalculate the site response. The low frequency level and corner frequency of seismic source spectrum are inversed and the new seismic parameters (seismic moment,stress drop,rupture radius) taking part in the inversion are calculated. In the meantime,the relationships between them are discussed. The inversion results indicate that the relationship between average Q value of Fujian area and the frequency is Q=504.1×f^0.332,and the site response is around 1 and correlated to frequency.This result is coincident to the situation that Fujian digital seismic stations are almost built on the bedrock. Calculations of seismic source parameters suggest that there is good correlations between seismic moment and seismic magnitude,while the correlations between seismic moment and stress drop,the stress drop and source radius are not so well,due to,possibly,the lack of the quantity of earthquakes and the limit of seismic magnitude that take part in the inversion.

FEATURES OF ACTIVE TECTONICS AND RECURRENCE BEHAVIORS OF STRONG EARTHQUAKES IN THE WESTERN SICHUAN PROVINCE AND ITS ADJACENT REGIONS

XU Xi-wei, ZHANG Pei-zhen, WEN Xue-ze, QIN Zun-li, CHEN Gui-hua, ZHU Ai-lan

2005, 27(3):  446-461. 

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There exist several groups of seismogenic active faults at the conjoined areas of the Chuandian,Bayankala and Huanan active blocks along the eastern margin of the Qinghai-Tibetan Plateau. Owing to existence of transverse secondary active faults,the Chuandian Block can be further divided into the Middle Yunnan and Northwestern Sichuan sub-blocks,and the Longmenshan sub-block at the easternmost end of the Bayankala Block. Joint exploration of the crustal structure shows that low-velocity layers exist in the crust of the Chuandian and Bayankala Blocks. These low velocity layers correspond also to high conducting layers and they are the cause of frequent earthquake occurrence in the upper crust. Geologic study and GPS surveying indicate that the tectonic motion of the blocks in this region is accounted to be a complex or superimposition of three basic types of motions: southeastward sliding,rotating on vertical axis,and uplifting,but there is difference in the geologic slip rate and GPS rate. Besides,this paper collects the database of the geologic slip rates and GPS slip rates for the active faults in the region and major scientific problems are also discussed at last.

A FRACTAL STUDY ON THE PYROCLASTS FROM THE LONGGANG VOLCANO, JILIN PROVINCE

ZHANG Bing-liang, BAI Zhi-da, HONG Han-jing, XU De-bin, PAN Xiao-dong

2005, 27(3):  462-469. 

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The field investigation shows that the volcanism in Longgang,Jilin has three distinct eruption ways,i.e. phreatic eruption,phreatomagmatic eruption and magmatic eruption. The materials of phreatic eruption are rock fragments from basement or volcanic channel with a grain size less than 5mm and nearly isoaxisal shape. The products of phreatomagmatic eruption include basaltic pyroclasts and rock fragments of basement with greatly different grain sizes and isoaxial structure. The magmatic eruption generates blowhole-shaped pyroclasts which are of grain sizes 8～0.5mm,mostly nearly equi-axial structured and some being non-equiaxial. Based on the fractal theory,we analyze the fractal features of the grain size of pyroclasts from the Longgang volcanoes,Jilin Province. Our results show that the fractal dimension of the pyroclasts of phreatomagmatic eruption is smaller than that of the phreatic eruption,but greater than that of the magmatic eruption. The values of fractal dimension can be used as parameters to distinguish different types of volcanic eruption. For the Longgang volcanoes,the fractal dimension of pyroclasts at Jinglongdingzi on the upper profile over the water resisting layer is greater than 2,and those at Xiaojinglongdingzi on the lower profile is less than 2. Fractal dimension values can be regarded as an indicator to differentiate various eruptive sources and to classify stratum sequences associated with volcanoes. Our research demonstrates that the pyroclasts with fractal dimension less than 2 contain anisometric grains of various content,and their values of fractal dimension are negatively correlated with the grain content. This is the first time to study the fractal dimension of the grain sizes of pyroclasts for this area. It suggests a new approach to distinguishing eruptive types,strata sequence and eruption intensity of volcanoes in a quantitative manner.

MAPINFOR-BASED 1/500000 DIGITAL GEOLOGICAL MAP DATABASE OF THE PEOPLE'S REPUBLIC OF CHINA

ZHANG Wei-hua, LIAN Chao, CHEN Hao, LI Sheng-le

2005, 27(3):  470-478. 

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By studying the MAPGIS-based management system of the 1/500000 digital geologic map database of the People's Republic of China,we focus the study on the search codes of geological and geographic factors and establish the coding rules for retrieval. The database'search code is composed of geologic factor and geographic content. The geologic factor search code includes: chronostratigraphy,geologic borderline and fault,genesis type,metamorphic rock,intrusive rock,volcanic rock,well core,isotope and crater age,logic hierarchy and so on. Geographic content search code includes eight parts,namely,the inhabited area,river,lake,border,communication,culture,ocean,and the others. In this paper,we also give the fields for data of each type and for retrieving. For the convenience of MapInfor users,the authors convert the data format of the database management system into MapInfor format,and adopt Visual Basic 6.0 to transform the MAPGIS-based database management system of the 1/500000 digital geological map of the People's Republic of China into MapInfor platform. The software include: [FILE],[SPACE SCOPE SEARCH],[GEOGPHIC CONTENT SEARCH],[GEOLOGIC FACTOR SEARCH],[EXIT]. At last,instructions are attached on how to use the 1/500000 digital geological map of the People's Republic of China based on MapInfor platform.

GHM-LIKE ORTHOGONAL MULTIWAVELET TRANSFORM AND ITS APPLICATION TO DE-NOISING OF SEISMIC DATA

CHEN Xiang-peng, CAO Si-yuan

2005, 27(3):  479-486. 

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Multiwavelet is a new development in the wavelet theory and it can offer simultaneously orthogonality,symmetry,and short support. In signal processing,the orthogonality preserves energy,the symmetry avoids signal distortion and the short support reduces the boundary effects. Therefore multiwavelet is very suitable for various signal processing applications,especially denoising. The paper presents multiwavelet principles,transformation procedures,pre-processing methods and proposes a new GHM-like multiwavelet-based denoising method. In seismic data processing,the attenuation of random noise is an important research subject. Conventional temporal or spatial filtering methods often damage the useful signals while suppressing noise,and the single wavelet transforms can cause signal distortion since it fails to offer simultaneously the orthogonality and symmetry. The paper adopts multiwavelet and multiresolution method to remove noise contained in seismic data. Seismic data is first preprocessed to generate a group of vector data,and then approximate and detailed signals of various scales are generated by two-level multiwavelet transformation. Finally detailed signals are processed by soft threshold and denoised seismic data are obtained by reverse multiwavelet transformation. The denoising experiments of synthetic and real data show that multiwavelet transform is effective for noise reduction and can preserve signal features at the same time.

INTELLIGENTIZED NETWORK SEISMIC MONITORING AND REALTIME DATA PROCESSING SYSTEM

LEI Dong, ZHI Hong-kui, HU Xiang-yun, ZHANG Xiang-rong, XUE Hong-xuan, ZHANG Su-fang

2005, 27(3):  487-492. 

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As we know,the SSDP mutual analysis software for seismic data processing has been widely used in many digital seismic stations in China. However,some inefficient functions in the software have limited its applications,namely: (1)Seism containing lg seismic phase cannot be located. (2)Magnitude m_B and m_b cannot be calculated. (3)Seismic catalogue cannot be generated automatically. (4)It depends on other software (for example SSB) to do the seismic instant report and the seismic data cannot be shared. (5)Precision in calculating local seismic parameters can't be guaranteed. (6)Epicenter can't be showed in the map. As a solution to these problems,we developed a new intelligentized network system based on VB (Visual Basic) for seismic monitoring and data processing. Compared with SSDP system,we added some new functions to the system,such as real-time monitoring of working status of seismic equipment,seismic parameters calculation and instant seismic reporting by itself. The implements also include searching of seismic events,automatic editing of seismic catalogs,analyzing of seismic phase and transmitting data. Our software has been used effectively in the Luoyang Station of Henan province over one year. It is able to deal with all daily works and alleviate the workload in digital seismic station,and it is helpful in improving the quality of seismic monitoring. The advantage of digital seismograph has been brought into full play.

APPLICATION OF ORACLE ADVANCED QUEUE ON TRANSMISSION OF SEISMOLOGIC PRECURSOR OBSERVATION DATA

SHI Wei, LIU Zhi, XU Hong-tao

2005, 27(3):  493-499. 

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As far as the seismological research is based on observation,huge seismic precursor data are produced at earthquake stations. It is vital to send them precisely and betimes. During the period of the Ninth Five-Year Project of China Seismological Bureau,several methods were applied to transmitting seismic precursor data,such as advanced replication,FTP,E-mail and etc. The advanced replication is used more extensively than others. But data are often lost by advanced replication. So a new transmission method has to be found to meet the need. This paper presents the advanced queuing method for transmitting seismic precursor data. Advanced queuing has a unique database-integrated message queuing feature built on the Oracle Streams information integration infrastructure. With Advanced Queuing,message queuing operations can be performed in the way similar to SQL operations from the Oracle database. Message queuing functionality allows applications of Oracle database to communicate asynchronously via messages in AQ queues. With the development in seismic precursor observation in China,more knowledge on the characteristics of seismic precursor data has been gained,for instance the data sources are complex,the data structure is diversified,the data sampling rate is not consistent. In order to transmit seismologic precursor data,a standard data structure needs to be created. The transmission is either point to point or point to multi-points. The system is programmed by PL/SQL. Both the sending host and the receiving one are installed with Oracle9i version. The result shows that it can transmit seismic precursor data from earthquake station to provincial center safely and reliably by using advanced queuing. It also has additional advantages compared with before. Firstly,it can assign priority to data,and then transmit the urgent data of higher priority; Secondly,it is easy to manage the advance queue with Oracle Enterprise Manager. But the network bandwidth is still the bottleneck of the transmission.

AN INTEGRATION MODEL OF EARTHQUAKE PREVENTION AND DISASTER REDUCTION INFORMATION SYSTEM BASED ON WEB SERVICES

ZHOU Na, LIU Zhi, WANG Li-yun, WANG Li-hong, ZHU Yan-min, HAO Yong-wei

2005, 27(3):  500-512. 

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Earthquake Prevention and Reduction Information System (EPRIS) includes Seismometry Sub-System,Strong Motion Sub-System,and Active Fault Sub-System and so on. These sub-systems are independent,hetero-structured and cross networked. They are based on different platforms and developed by different programming languages. There is lack of commutation and collaboration among them. At present,CEA plans to build a self-contained Chinese Digital Seismic Networks System in which new operations and new platforms are brought forward. How to protect the existing investment and realize integration between the old systems and new systems is a pending question. In view of independence,hetero-structure and cross-network of EPRIS,a Webservice-based integration model is proposed for EPRIS and a case study is performed in the paper. The Web Services technology is independent of programming language and all kinds of platforms,so it can solve the above-mentioned problem.