大地测量与地球动力学
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Current Issue
2009 Vol.29 Issue.3
Published 2009-08-28
地壳形变与地震
1
DYNAMIC GRAVITY CHANGE IN RECENT YEARSIN CHINA CONTINENT
Li Hui;Shen Chongyang;Sun Shaoan;Wang Xiaoquan;Xiang Aimin;and Liu Shaoming;
The paper introduces the mobile gravity measurements of the Crustal Movement Observation Network of China and Digital Earthquake Observation Network of China since 1998. The patterns of gravity change in 2-3 year time scale are given
and the character of gravity changes along with the current crust movement and strong earthquake occurring are primarily analyzed. The results show that the gravity changes basically reflect the outline of the current mass movement and strong earthquake occurring in China continent.
2009 Vol. 29 (3): 1-10 [
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2538
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11
GRAVITY EFFECT FROM PRESENT ACTIVITY OF NORTHERN SEGMENT OF RED RIVER FAULT ZONE
Sun Shaoan;Shen Chongyang;and Xiang Aiming;
By finely handling a batch of gravity difference data in the northern segment of the Red River fault zone, we found the temporal variation of these gravity differences in the period from 1985 to 2006. The research results show that: 1)The fault activity is cyclical by alternatelly being strong and weak, and in the two different processes both of the extrusion degree and time duration are different. 2) The fault activity has obviously segmental character that the fault activities in JianchuanXiaguan are basically the same and Dingxiling is the indicative place; in Midu, however, there is a varying law of being mirror relationship with JianchuanXiaguan. 3)The gravity change caused by fault activity comes mainly from the density change of underground substances, and the crustal deformation, which howevery can be ignored for it is rather weak.
2009 Vol. 29 (3): 11-15 [
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2641
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16
P315.73P315.73NEGATIVE DISLOCATION MODEL OF VERTICAL CRUSTAL MOVEMENT AND BACKGROUND BEFORE WENCHUAN AND PANZHIHUA EARTHQUAKES
Zhang Xi;Zhang Sixin ;and Wang Shuangxu
By use of the regional leveling observations of the western Sichuan in the periods of 1990—1997, 1997—2003 and 1994—2006 and the aid of inversion of negative dislocation，the characteristics of tectonic deformation and strain accumulation background of correlative and neighbor faults before the Wenchuan Ms8.0 earthquake and the Panzhihua Ms6.1 earthquake are researched. It is concluded that there is obvious uplift in the large region according with its background of successive movement and longterm (over 10 years) strain accumulation on the northern segment of Anninghe fault and the southern segment of Xianshuihe fault and the region they meet Longmenshan fault，reflecting the background of the Wenchuan Ms8.0 earthquake to some extent.Moreover, the acceleration of stain accumulation during 1997—2003 on the southern segment of Yuanmouluzhijiang fault may reflect the background of the Panzhihua Ms6.1 earthquake.
2009 Vol. 29 (3): 16-23 [
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2737
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23
ON CHARACTERISTICS OF CRUSTAL MOVEMENT OFSHANDONG AND SURROUNDING AREAS BEFOREAND AFTER WENCHUAN \%M\%s8.0 EARTHQUAKE
Yin Haitao;Li Jie;Dong Xiaona;and Xu Ping
In order to study the crustal movement of Shandong and surrounding areas before and after Wenchuan \%M\%s8.0 earthquake, we analyzed the baselines between Taian(TAIN) and several fiducial stations in different blocks by using SDFT Period Estimate method. The preliminary results showed that there were obvious exceptional annual variations of baseline TAINXIAN and TAINWUHN before Wenchuan earthquake. The eastward movement velocity of GPS fiducial stations in Shandong and surrounding area was decreasing after the earthquake, we conclude that the eastward driving force on the North China block weakened, It shows that the Wenchuan earthquake alleviated the Shandong and surrounding areas’ recent earthquake situation.
2009 Vol. 29 (3): 23-27 [
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2572
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28
RESPONSE OF WELL LEVEL TO CRUST BODY STRAIN CAUSED BY WENCHUAN Ms8.0 EARTHQUAKE
Liu Xuyan;Li Jun;Zheng Xiaojing;and Wang Lin
The wellwaterlevel system is a natural body strain gauge. Taking the theoretical earth tide value of body strain as the input of the system and digital observations of well level of the system as the output, the harmonic analysis results of the digital observation of well level computed with Venidikov’s harmonic analysis method is transfer function(sensitivity) of the well level system. The paper takes the amplitude factor of wave M2 as the theoretical calibration value η of well level system.The waterlevel shock wave
excited by Wenchuan s8.0 earthquake is calculated by use of the minute values of water level of five wells in May,2008.
Meanwhile, the Rayleigh wave data
including the maximum amplitude of radial and vertical displacement and its periods,are recorded by seismograph.Body strain wave excited by Wenchuan earthquake is calculated with displacement divergence formula.
The result is the volume strain from seismograph which is high frequency is ten times bigger than the one from wellwaterlevel system which is low frequency.The difference between them is discussed at last.
2009 Vol. 29 (3): 28-33 [
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2454
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34
STUDY OF RELATIONS BETWEEN ANOMALY OF SHORT LEVELING AT JINGYANG STATION AND EARTHQUAKES
Ke Chang’an ;Li Zhengyuan ;Dou Mali ;and Liu Chun
It was found that the abnormal changes of short leveling data at Jingyang station, Shanxi province appeared,
which downslide southward in three months before Wenchuan Ms 8.0 earthquake. The similar phenomena appeared before the October 24,1995 Wuding Ms 6.5 earthquake,Yunnan, the December 18,1995 Maduo Ms 6.2 earthquake,Qinghai and the February 23,2001, Yajiang Ms 6.0 earthquake, Sichuan. The relation among magnitude (M), epicentral distance (L), anomaly amplitude (H) and anomaly duration (T) is M=0.002 8L＋1.126 9H＋0.076 8T by inversion method.
2009 Vol. 29 (3): 34-37 [
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1783
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38
MIDDLE AND LONGTERM SEISMIC RISK EVALUATION OF SOUTHERN SICHUANYUNNAN REGION BASED ON GPS DATA AND REALTIME PROBABILISTIC MODEL
Zhang Xiaoliang;and Xie Furen
We calculated the recurrence intervals of characteristic earthquakes of major active faults in southern SichuanYunnan region
with GPS data method and seismic moment method and the characteristic earthquake probabilities derived from realtime models in the future 10 a,30 a,50 a and 100 a. The results show that the values of probability for earthquake recurrence in the southern SichuanYunnan region are as follows: Xiaoxiangling segment of Anninghe fault，Dongchuan segment of Xiaojiang fault, MianningXichang segment of
Anninghe fault，Zemuhe fault, LijiangNinglang segment of LijiangXiaojinhe fault, Huaning and SongmingYiliang segments of Xiaojiang fault and northwestern segment of Red River fault.
2009 Vol. 29 (3): 38-41 [
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2940
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42
CHARACTERISTICS OF SURFACE DEFORMATIONCAUSED BY FAULT DISLOCATION
Tan Hongbo;Shen Chongyang;Li Hui;and Li Ji;
According to the theory of surface deformation caused by the dislocation on a rectangular fault within an isotropic homogeneous halfspace, the characteristics of surface deformation caused by one fault or combination of two faults are studied. The main conclusion
are as follows: 1) For one fault, the characteristics of surface deformation and the pattern of dislocation is closely related. The depth of fault, the dip angle and the magnitude of dislocation(U1,U2,U3) have grate effects on the deformation as well. 2) For the combination of two faults, when they are in the same depth, the relative position of the faults have great effect on the surface deformation; when they are in different depth, the shallow fault plays a dominant role in the total surface deformation.
2009 Vol. 29 (3): 42-49 [
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2717
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50
STUDY ON METHOD OF DETECTING IONOSPHERIC TEC ANOMALY BEFORE EARTHQUAKE
Zhu Fuying;Wu Yun;Lin Jian;Zhou Yiyan;Xiong Jing;and Yang Jian;
Considering the limitations of available methods including the method on median and the Inter Quartile Range (IQR),etc. for detecting the abnormal TEC disturbance of ionosphere before earthquake, the paper put forword an improved method to distinguish the TEC anomaly by use of
residual error after fitting the ionospheric TEC,i.e. At first,fitted the time sequence of ionospheric TEC and then distinguished the anomaly with sliding window method.
On the basis of the GNSS observation data from the reference stations of Crustal Movement Observational Network of China, the continuous 31day TEC values over China were computed and the data of Wenchuan Ms8.0 earthquake in Sichuan province on May 12th 2008 were analyzed, the results shows that the ionospheric TEC anomaly obtained with the method is reasonable and effective.
2009 Vol. 29 (3): 50-54 [
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2581
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55
ENVIRONMENTAL EFFECTS ON GRAVITY AND VERTICALDISPLACEMENT OBSERVATION AT WUHAN STATION
Zhou Hongwei;Xu Jianqiao ;Sun Heping ;and Zhou Jiangcun
The relation between gravity variations, vertical displacement variations and the major environment factors is studied by using the continuous observational data with superconducting gravimeter and GPS at Wuhan station. According to the surface loading theories of classical elasticearth the contributions to the gravity and vertical displacement from atmosphere loading, nontidal oceanic mass and continental water loading were simulated and calculated. The numerical results show that the annual amplitude variations of gravity and vertical displacement are mainly caused by abovedmetioned three kinds of environment factors, the contributions are 90% and 75% respectively. At present the global assimilation models of land water such as LaD and GLDAS cannot objectively reflect realtime changes in water storage in the site of local stations, as there is timedelay between calculated values and observations.
2009 Vol. 29 (3): 55-59 [
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2559
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60
RESEARCH ON DEFORMATION CHARACTERISTICS OF WEIHE BASIN
Gao Haolin ;Zhu Yiqing ;Han Meitao ;Dou Mali ;and Li Jing
The relations between the differences of crustal deformation of Weihe basin leveling profile from 2001 to 2008 and active fault, distribution of cities and towns,underground water level are analyzed, the differences between vertical fracture activity rate gradients on the same or different faults are studied. The activity characteristics that the trend of profile deformation is slow in Weihe basin and meanwhile there is a reverse change in the north to Jingyang since 2004 are discussed.
2009 Vol. 29 (3): 60-66 [
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2040
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67
INFLUENCE OF TOPOGRAPHY ON GRAVITY ANOMALY OF SUBDUCTION ZONE
Wang Wei;Ning Jinsheng;Wang Haihong;and Luo Jia;
Abstract\ [WT]Taking Manila trench subduction zone as an example,this paper has a research on the gravity anomaly of subduction zone with wavelet analysis. Through Symlet wavelet multiscale analysis of the data of gravity anomaly and topography around the subduction zone we
have found that there is a close relationship between gravity anomaly and topography in the fourth or the fifth scale of high frequency, and surmised that the seawater influences mainly in the second and the third scale of the high frequency of gravity anomaly, which provides a reference for dividing the influence of noise, seawater, topography and so on.
2009 Vol. 29 (3): 67-69 [
Abstract
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1911
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70
DATA ANALYSIS OF GPS SLIDE MONITORING NETWORK IN ZIGUI ZONE OF THREE GORGES RESERVOIR AREA
Liu Genyou ;Xue Huaiping ;Hao Xiaoguang ;Guo Aizhi ;and Yi Qinglin
Two sessions of GPS observations of ten GPS monitoring stations located at the strong landslip i.e. XiangxiYemaomian zone in Zigui region of Three Gorges from 2005 to 2007, were calculated by use of three schemes of parameter constrain adjustment method
including classic adjustment, quasistable adjustment and adjustment of freedom network and two sessions of displacement were obtained.At last,the stability of these monitoring points are discussed.
2009 Vol. 29 (3): 70-73 [
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2368
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74
APPLICATION OF PHASE INFORMATION TO SIGNAL DETECTION OF ARTIFICIAL SEISMIC SOURCE
Tang Jie ;Ge Hongkui ;Wang Baoshan ;and Chen Yong
]In recent years more and more artificial sources are used to explore underground structures in the regional scale deep exploration.Usually, signals from artificial seismic source have low SNR(signal to noise ratio). Artificial source has a certain degree of repeatability among different shots.
On the basis of this character, we use phase crosscorrelation and phase weighted stack which can effectively improve the clarity of the signal to detect weak signal.
The study shows that by use of dozens of kilograms of explosives the signal can be detected from the distance of 200 km.
2009 Vol. 29 (3): 74-76 [
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2976
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77
COMPARATIVE OBSERVATION OF ABSOLUTE GRAVIMETERS IN WALFERDANGE
Xing Lelin;Shen Chongyang;Li Hui;and O.Francis
The European comparison of absolute gravimeters held in Walferdange, Luxembourg in November 2007 are reported. 20 absolute gravimeters including the FG5/232 of CEA to take part in the comparison and the standard deviations of gravity data from 15 stations are less than 2.1 ×10
-8
ms
-2
. The method of data processing and the analysis of results are described.
2009 Vol. 29 (3): 77-79 [
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2040
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理论方法研究
80
EFFECT OF HEIGHT DIFFERENCE ON GPS VERTICAL ACCURACY
Dai Wujiao;Chen Zhaohua;and Liang Ming
When the height difference between the ends of the baseline is large, the tropospheric delay can not be mitigated by the
usually used double difference technology even if the length of the baseline is short. It is caused by the different weather condition between the ends of the baseline with large height difference. In order to analyze the height difference effect on GPS vertical accuracy, the several computing tests were carried out by using the data from Hong Kong GPS reference network. Some conclusions can be drawn from these test results. The first, the residual tropospheric delay will be big without using empiric tropospheric delay model and standard atmosphere model when the height difference is large. The second, the errors of meteorology observation on sea level will bring about some errors in GPS vertical direction even the empiric tropospheric delay model and standard atmosphere model are used. The third, observations for a long time can smooth some stochastic effects of the residual tropospheric delay.\
2009 Vol. 29 (3): 80-83 [
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2911
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84
GPS HEIGHT CONVERSION BASED ON BAYESIAN REGULARIZATION BP ARTIFICIAL NEURAL NETWORK
Zhang Qiuzhao ;Zhang Shubi;Liu Jun ;Wang Guanghui ;and Wang Bo
In view of the defects of traditional BP artificial neural network, the Bayesian regularization method is used for improving the generalization ability of artificial neural network. Through an engineering example, the BP artificial neural network method with Bayesian regularization is compared with LM method and polynominal curve fitting method respectively. It is found that the improved method has better fitting precision, stability and better generalization ability,so it has good practicability in GPS height conversion.
2009 Vol. 29 (3): 84-87 [
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2967
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88
CALCULATION AND FORMULA DEDUCTION OF MAGNETIC DECLINATION AND GEOMAGNETIC INCLINATION
Wang Jiexian;and Li Haojun
Magnetic declination is the angle between magnetic north and true north, the angle will change with the variation of latitude, longitude and height. The relation between magnetic meridian azimuth and true azimuth is discussed, and the calculation formula of magnetic declination and geomagentic inclination are deduced when the latitude,longitude and height are known.At the same time,the magnetic declination and geomagentic inclination in China are calculated, and their variation rules with the variation of latitude, longitude and height are analyzed.
2009 Vol. 29 (3): 88-90 [
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3722
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91
APPLICATION OF GREY MODEL BASED ON BUFFER OPERATOR TO CRUSTAL DEFORMATION FORECASTING
Xu Junyi; and Zeng Anmin
The GM(1,1) model is generally founded on the position information when it is used in local crustal deformation prediction. However, it can not fully reflect the change of points.Therefore the GM(1,1) model based on buffer operator is proposed. The position sequence of crustal deformation is preadjusted by buffer operator according to the qualitative analysis of the velocity information before forecasting. By using the real data processing as an example, it is revealed that the prediction accuracy is greatly improved.
2009 Vol. 29 (3): 91-94 [
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2717
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95
COMPARISON AMONG THREE SPATIOTEMPORAL FILTERINGMETHODS FOR REGIONAL GPS NETWORKS ANALYSIS
Hu Shouchao;Wu Jicang;and Sun Yafeng
Three regional filtering methods:stacking, principal component analysis and KarhunenLoeve expansion, were respectively applied to analyze the time series of daily coordinate for five years from twelve stations of Southern California integrated GPS network. The results indicate that the common mode errors can be extracted with all three methods and thereby the precision of coordinates will be improved remarkably, but they have respective advantages and disadvantages.
2009 Vol. 29 (3): 95-99 [
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2692
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100
SINGLE EPOCH GPS POSITIONING BASED ON TRACK MODULE
Su Xiaoning ;Meng Guojie ;Hu Congwei ;and Wu Jicang
1 Hz and 3 second sampling GPS data of 2 moving objects using the kinematic module TRACK of the GPS data processing software GAMIT had been processed, and well obtained the true trajectory of the buoy on sea and moving target in the air. In the case of static positioning, the GPS data of 3 baselines had been proccessed, which are of less than 10 km ,between 10 and 100 km, as well as more than 100 km. Accuracy analyses were also carried out. Statistic results show that in the case of high quality of data, the accuracy of horizontal components can reach or be close to 5 mm.
2009 Vol. 29 (3): 100-103 [
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2028
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104
APPLICATION OF T/P ALTIMETER BACKSCATTER DATA TO LAND SURFACE OBSERVATION
Chu Yonghai;Li Jiancheng;Jin Taoyong ;and Wang Haihong;
By use of the Topex/Poseidon radar altimeter data for 13 years,the time series of backscatter coefficient of
Greenland ice sheet, the Amazon basin tropical forest and Congo tropical forest, TaklaMakan desert and UbariMurzuq sand sea in Libya, Siberian steppe and North Dakota temperate grassland are discussed. It is found that the time series of Ku and C wave bands and its difference reflect the relations between surface covering, climatic environment and backscatter coefficient.
2009 Vol. 29 (3): 104-108 [
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2968
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109
TURBOEDIT ALGORITHM AND ITS IMPROVEMENTS INUBDIFFERENTIATED PHASE DATA PREPROCESSING
Yuan Yubin ;Dang Yamin;Cheng Yingyan ;and Zhou Guomeng
Three improvements of TurboEdit algorithm are made. The effects of different arc sections, the length of arc section and gross errors are taken into account in calculating widelane ambiguity and its variance. It is by analyzing three successive epochs that both of the combination observations determine whether the current epoch is a gross error or cycle slip.
A new fitting model based on sliding window is put forward, which is more suitable for the fact that GeometryFree combination observations constitute a smooth time series. The secondary processing for divided GF arc sections can further reject gross errors. The experimental results show that the new algorithm can detect and fix the equaldistance, equalcycle and continuing happened cycle slips, can also reject successive gross errors and those less obvious gross errors.
2009 Vol. 29 (3): 109-113 [
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114
GENERALIZED SHRUNKEN T-TYPE ESTIMATIONIN GUASSMARKOV MODEL
Chen Ke ;Gui Qingming ;and Yang Na;
Ttype estimation is a new kind of robust estimations, which takes tdistribution as the error distribution and has some advantages in some respects.The equivalent weight form of ttype estimation is presented. A disadvantage of ttype estimation that it cannot resist illconditioning is analyzed. To overcome this drawback, according to the idea of the generalized shrunken type robust estimation, the generalized shrunken ttype estimation is presented, which shrinks the solution of the location parameters. Some important
problems of this estimation are discussed. A numerical example shows the validity of the method presented.
2009 Vol. 29 (3): 114-118 [
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119
VARIATIONS OF LOD INFERRED FROM TEMPORAL GRACE GRAVITY DATA
Chen Wei;Shen Wenbin;Li Jin ;and Han Jiancheng
The impacts of the temporal secondorder potential coefficients on the Earth’s principal axes and moments of inertia as well as variations of length of day (LOD) are studied. By using the wavelet analysis and adoption the monthlyaveraged GRACE gravity model,
the secondorder potential coefficients were processed and the jumps and noises presented in these data were removed. After comparing the Earth’s principal axes and moments of inertia obtained from the processed with those from the nonprocessed coefficients, the associated variations
of LOD were obtained based on the processed data. Numerical calculation results show that the mass redistribution related to the monthly temporal principal axes and moments of inertia could lead to a decreasing tendency of LOD during the recent 6 years.
2009 Vol. 29 (3): 119-124 [
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2983
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125
REFINING OF CENTIMETER-PRECISE LOCAL QUASI-GEOID
Deng Biao ;Hong Shaoming ;and Song Lei
From the determination of the data of quasigeoid, the paper mainly explores the techniques for local quasigeoid refining.As applying them to engineering projects the accuracy of cedimeter level can be reached.
2009 Vol. 29 (3): 125-127 [
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128
DEDUCTION OF BESSEL MEAN SQUARE ERROR FORMULA
Deng Yonghe
Several methods of testifying Bessel mean square error formula introduced in Chinese teaching materials of surveying and mapping are summed up. A better method to improve and unify teaching material, and to be understood easily for students is recommended.
2009 Vol. 29 (3): 128-130 [
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131
INVERTION OF CRUSTAL THICKNESS OF MOONFROM GRAVITY FIELD AND TOPOGRAPHY DATA
Feng Hai ;Li Jiancheng ;Zhang Shoujian ;and Xing Lelin
The gravity anomalies are mainly resulted from three factors: terrain gravity effects,mare basalts fill and Moho relief attraction. The terrain model GLTM2 and the lunar gravity field model LP165 are used to estimate the crustal thickness between ±60° latitude of the nearside with the assumption that the thick of mare basalts fill is neglected. Additionally, a combinated crustal map is obtained. On the basis of the results the following conclusion can be drawn out: that the crustal thickness of the nearside of the Mon is between 15 km and 76 km, and the average is 48.6 km. It also shows that a generally thinner crust beneath the mare basins than regions around.
2009 Vol. 29 (3): 131-134 [
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1915
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135
STUDY ON METHOD OF InSAR COMBINED BASELINE ESTIMATION
Fan Hongdong;and Deng Kazhong;
On the basis of analyzing the relations between positioning and deformation measuring accuracies and baseline error, the importance of baseline estimation was pointed. By comparing and combining three classical baseline estimation methods, a new baseline estimation method and its flow were proposed, and the estimation accuracy affected by squint angle also was researched quantitatively. Finally, by comparing and analyzing the interferograms and sample altitudes generated with different baseline combination methods, the correcness and feasibility of the proposed baseline estimation method are validated.
2009 Vol. 29 (3): 135-140 [
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2914
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141
ANALYSIS AND IMPROVEMENT OF ACCURACY OF GPS POINT POSITIONING OBSERVATIONS
Wang Ping ;Hao Jinming ;Sheng Guokang ;and Wang Haoyu
The relation between the accuracies of ionofree combination pseudorange observation and P code pseudorange observation is analyzed. The experiment results show that when the qualities of P1 and P2 code pseudorange are very different, the accuracy of the ionofree combination pseudorange declines, as a result, the accuracy of point positioning using ionofree combination pseudorange is worse than that of point positioning using P1 code pseudorange . In order to solve the problem, a new point positioning method is proposed. The key of this new method is to determine the observation which should be used at every epoch. If the accuracy of P1 and P2 code pseudorange are similar, the ionokfree combination pseudorange should be used. Otherwise, the P1 code pseudorange. The experiment results show the new method can improve the point positioning accuracy effectively.
2009 Vol. 29 (3): 141-144 [
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观测技术
145
DEVELOPMENT OF DIFFERENCE EXTENSOMETER
Lu Chongwu;and Yang Jiang
The structure,principle of the difference extensometer and the experimental results are introduced. The results show that difference extensometer is better than available instruments in the capability for antijamming, especially, it can particularly restrain the interference of common mode from the environmental vibration, the power fail in a moment and power noise.
2009 Vol. 29 (3): 145-147 [
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2737
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148
WebGIS APPLICATION SCHEME FOR EARTHQUAKE PRECURSORY INFORMATION
Wang Xiuying;Zhou Zhen’an;and Liu Aichun
After the completion of ‘the tenth fiveyear plan’ project for the earthquake precursory observatory system, it is the focus of the application of earthquake precursory information to develop data sharing application.It has summaried the data types of the earthquake precursory information which can be used by WebGIS application and a WebGIS application scheme which adapts itself to the current running earthquake precursory system is given also. An instance based on this scheme is discussed to demonstrate that this scheme can be implemented and makes user more convenient and is efficient to use the earthquake precursory information.
2009 Vol. 29 (3): 148-151 [
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2404
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