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Relocation of the 2023 MS6.2 Jishishan Earthquake Sequence in Gansu Province ZUO Ke-zhen, ZHAO Cui-ping EARTHQUAKE    2024, 44 (1): 204-208.   DOI: 10.12196/j.issn.1000-3274.2024.01.018 Abstract （42）      PDF（pc） （2030KB）（85）       Knowledge map    This study used the double-difference earthquake location method combined with waveform cross-correlation technique to relocate the MS6.2 Jishishan earthquake sequence (As of 24:00 on December 22, 2023) in Gansu Province. The results show that the epicenter of the MS6.2 Jishishan earthquake is located at Jishishan County, Linxia Prefecture (35.745°N, 102.827°E) and the focal depth is about 12.5 km. The aftershock sequence formed two branches in different directions, which were NW and NNW. The aftershocks near the MS6.2 Jishishan earthquake are distributed in an NW direction, and tilted toward the NE. The relocation results reveal the complex tectonic environment of the region.

A Review of Foreshock Research ZHOU Shao-hui, JIANG Hai-kun EARTHQUAKE    2016, 36 (3): 1-13.   Abstract （204）      PDF（pc） （2028KB）（388）       Knowledge map    This paper briefly introduces current progress in the field of foreshock research, both in China and abroad. We contrast common characteristics and the mechanism of foreshocks and foreshock sequence under the different definitions of foreshocks. The main recognition methods of foreshock and its characteristics and existing problems are reviewed and discussed. Foreshocks are small earthquakes that occurred before the mainshock and adjacent to the main source location. Foreshocks sequence is consisted of a series of foreshock activities occurred before the mainshock. The proportion of earthquake cases includes direct foreshock ranged from 10~40% at different defined conditions of foreshock. Theoretically, cascade model or pre-slid model can explain foreshock. Foreshocks are mainly concentrated in the range of 10~75 km off the mainshock, but its time distribution form is very complicated, mostly 1 to 2 days before mainshock, the seismicity rate of part of foreshock sequences show significant acceleration features, but many foreshock sequences often show attenuation characteristics of mainshock-aftershock sequences. The most prominent feature of foreshocks is consistency of focal mechanism and low b value of earthquake sequence. Foreshocks seem to have a certain relationship with tectonic environment and the rupture form of mainshock, and in some cases, the dip-thrusting earthquakes seem to have relatively more foreshocks. Some earthquake cases show that focal depth of foreshocks gradually moves downward with the mainshock approaching. So far, it is difficult to determine whether an earthquake or an earthquake sequence is foreshock or foreshock sequence before earthquake, the identification method of foreshock mainly including statistical method of analogy, focal consistent mechanism and related derivative method, the fine detection of earthquake nucleation process. From the few existing studies of earthquake cases, in spite of temporal earthquake clusters and focal consistent mechanism are the most significant features of foreshock sequence, not sufficient condition for judgment foreshock sequence. Due to the rupture rate of expansion and sliding displacement have a tendency to increase faster over time, thus the method of the fine detection of earthquake nucleation process is expected to play a more important role in the identification of foreshock.

Disaster mitigation and earthquake disaster emergency management in Japan SHUAI Xiang-hua, YANG Gui-ling, JIANG Li-xin EARTHQUAKE    2004, 24 (3): 101-106.   Abstract （74）      PDF（pc） （375KB）（243）       Knowledge map    This paper introduced the related situation concerning the disaster mitigation and earthquake disaster emergency practices in Japan by focusing on its system and technology. Hyogo Prefecture Disaster Management Center and Tokyo Prefecture Disaster Management Center, the most representative in Japan, provide us a good example for improving our work on disaster mitigation and earthquake disaster emergency.

The Japan Noto Peninsula M7.6 Earthquake on January 1, 2024: Focal Characteristics, Disaster Situation and Emergency Response CHEN Guang-qi, WU Yan-qiang, XIA Ming-yao, LI Zhi-yuan EARTHQUAKE    2024, 44 (1): 141-152.   DOI: 10.12196/j.issn.1000-3274.2024.01.010 Abstract （54）      PDF（pc） （4280KB）（70）       Knowledge map    On January 1, 2024, a large earthquake with magnitude 7.6 struck the Noto Peninsula in Japan, causing significant casualties and property damage. This paper provides a quick analysis of the focal characteristics, damage and emergency response, using information in three days after the earthquake. The results show that: ① The rupture of the earthquake was thrust type, and the distribution of aftershocks showed a NE zonal character with ~150 km range. ② GNSS observed a significant west-northwest coseismic displacements in the epicenter annex, with maximum horizontal displacements of 1.2 m, and the two-segment fault inversion model was able to fit the observed data well. ③ The large PGV and PGA, with maximums of 145 cm/s and 2,681 cm/s2, were observed in the vicinity of the epicenter. This earthquake produced the highest value (7 degree) of the Japanese Intensity Scale near the epicenter, and all the areas in the Noto Peninsula were above 5+ (the Japanese Intensity Scale). ④ The recent earthquake has so far resulted in 73 fatalities and 323 injuries in Ishikawa Prefecture. Additionally, 183 buildings have been either completely or partially destroyed. The seismic event also triggered a series of cascading disasters, including tsunamis, fires, slope failures, and road damages. Finally, we briefly summarize the emergency measures in disaster response, including emergency relief and information dissemination. This work provides a reference case for understanding the mechanisms of earthquakes, studying the mechnism of disasters, and developing effective responses, further, provides lessons for handling similar events in the future.

A Review of Adjoint Tomography and Its Application in Earth’s Interior Imaging XIAO Zhuo, GAO Yuan EARTHQUAKE    2020, 40 (3): 52-64.   DOI: 10.12196/j.issn.1000-3274.2020.03.005 Abstract （565）      PDF（pc） （2947KB）（526）       Knowledge map    Numerical simulation techniques and adjoint method lead to the successful application of adjoint tomography in both regional and global full waveform tomography. Based on the spectral element method, adjoint tomography adopts full three-dimensional model as initial model for waveform modelling and calculates gradients efficiently through interaction between forward wavefield and adjoint wavefield. Owing to the power of high-performance computing, adjoint tomography utilizes full-wave tomography at large scale. Compared with traditional tomography techniques, adjoint tomography can describe the subsurface anomalies more detailed and comprehensively, so it is more favorable in deep dynamics research. Here we firstly introduce the basic theory of adjoint tomography, its workflow of implementation, and then we give a review of its worldwide applications, while finally a brief prospect of future developments is discussed at the end of this article.

Study on the Second Data Variation Characteristics of Geoelectric Field before and after Changning MS6.0 Earthquake XI Ji-lou, CHEN Min, DONG Lei, LIU Chao, GUAN Hua-ping EARTHQUAKE    2020, 40 (4): 129-143.   DOI: 10.12196/j.issn.1000-3274.2020.04.010 Abstract （179）      PDF（pc） （3641KB）（466）       Knowledge map    The geoelectric field is an important part of the earth electro-magnetic field. Using the traditional time series statistical analysis method, this paper studies and discusses the variation characteristics of the second sampling data of the geoelectric field observed from Xiannushan seismic station, which belongs to the Chongqing municipality. The results show that: ① before and after Changning MS6.0 earthquake, the anomalous change of the geoelectric field were recorded at Xiannushan seismic station, 390 km away from the epicenter; ② the average azimuth angle of the anomalous change was N77.55°E, approximately from the epicenter of Changning MS6.0 earthquake to Xiannushan seismic station; ③ the typical anomalous change of the geoelectric field was intermittent and non-periodic disturbance, which densely appeared 8 days before the main shock of Changning MS6.0 earthquake, lasted to the 4th day after the main shock, and then gradually transformed into the high-frequency disturbance changes; ④ the anomalous change of the geoelectric field appeared in lots of clusters, each of which is composed of multiple groups of step mutation with nonlinear attenuation. According to the comprehensive analysis, the anomalous change of the geoelectric field before and after Changning MS6.0 earthquake, may be related to the filtered electromotive force generated by the high-pressure migration of the underground fluid, during the change of the structural fracture and the process of the rock micro fracture.

Analysis on historic data of M$5\frac{3}{4}$ earthquake occurred in 1574 in Fujian Province ZHOU Zheng-rong, YUAN Ding-qiang, NI Xiao-yin EARTHQUAKE    2007, 27 (2): 139-146.   Abstract （93）      PDF（pc） （781KB）（312）       Knowledge map    There are great diversities of space and time recordation on the $5\frac{3}{4}$ earthquake occurred in August 1574 in Fujian Province on different catalogues and editions. This paper rechecks, analyzes and finds out the likely factors of existed difference through the historical data of different editions according to the time gradation. Combining the modern earthquake activities and the up to date earthquake safety assessment and analysis results, following the attitude of respecting historic data and scientific preciseness, the authors try to give the rechecking result of the 3 key seismic factors objectively. The result is that this earthquake occurred on August 19, 1574 between Fuzhou and Lianjiang with North latitude 26.1° and East Longitude 119.3°, and the more reasonable magnitude is $5\frac{3}{4}$.

Temporal and Spacial Variations of Apparent Stress in the Rupture Volume before and after the 2011 Tohoku, Japan, MW9.1 Earthquake LI Yan’e,CHEN Xue-zhong EARTHQUAKE    2017, 37 (4): 10-21.   Abstract （127）      PDF（pc） （980KB）（357）       Knowledge map    On 11 March 2011, the MW9.1 earthquake struck Tohoku, Japan. In order to investigate the temporal and special changes of apparent stress in the rupture volume of the mainshock, we selected 563 earthquakes (5.0≤MS≤6.9) located within the rupture volume which occurred between Jan., 1996 and Jun., 2016 to analyze the temporal variation and spatial distribution of apparent stress. It was found that the apparent stress started to increase at the middle of 2002, and reached to the highest value of 1.76 MPa from 0.6 MPa at the beginning of 2009, which increased about 3 times. Until when the 2011 Tohoku MW9.1 earthquake was drawing closer, the apparent stress kept above 1.5 MPa. From the occurrence of the Tohoku MW9.1 earthquake to Jun.2016, the apparent stress manifested a gradually dropping but kept above 1.5 MPa with the higher values. It showed that there were only individual higher values of apparent stress on the ground or the focal fault plane from 1996 to 2005, while there were lots of higher values of apparent stress in the rupture zone, from 2006 to Feb, 2011. In the three months after the occurrence of the Tohoku MW9.1 earthquake, the apparent stress was at a high value, and then, gradually dropped with a slow rate. Since the apparent stress is a lower bound for the average stress on the fault plane, higher values of apparent stress could show higher values of average stress on the fault plane. Therefore, it can be said that, before the Tohoku MW9.1 earthquake, the average stresses on fault planes of the rupture zone had been increasing for about 8.5 years. As a result, the stress in the rock of the rupture zone increased gradually before the Tohoku MW9.1 earthquake, which cause faulting and occurrence of the earthquake.

Extraction Method of Road Seismic Damage from Multi- source Remote Sensing Images and Application Prospect for Earthquake Emergency LI Qiang,ZHANG Jing-fa EARTHQUAKE    2017, 37 (4): 80-92.   Abstract （266）      PDF（pc） （488KB）（470）       Knowledge map    The road is the lifeline of relief after strong earthquakes, rapid and effective way to provide situation of disaster area can provide strong information support for distribution of earthquake emergency rescue force. Recognition of damaged road based on remote sensing image is difficult in the field of remote sensing earthquake emergency, but it has incomparable value for earthquake emergency. On the basis of summarizing and analyzing the characteristics of road image before and after earthquakes, this paper systematically introduces method of road extraction from remote sensing images. The process of building remote sensing seismic damage assessment is established, and the method of extracting and evaluating the road of remote sensing seismic damage is mainly described, and the shortage of remote sensing road extraction in earthquake emergency is analyzed. At last, the application of remote sensing technology in the extraction and evaluation of earthquake damage is also discussed.

Characteristics of Activity Periods for Shallow Earthquakes in Northeast China GAO Li-xin,DAI Yong EARTHQUAKE    2017, 37 (2): 115-125.   Abstract （206）      PDF（pc） （4210KB）（489）       Knowledge map    From the perspectives of energy of deep and shallow earthquakes and their energy release ratio as well as duration, the rhythm repetition of the end earthquakes of the fifth activity period and orderly activity image of moderate strong earthquake in the fifth activity period in northeastern China, we analyzed and compared characteristics with that of the former four periods. The results show that the energy release of the fifth activity period is far lower than other activity periods, energy release ratio of deep earthquakes and shallow earthquake is large, and the sustained time is long. The “closing door” earthquakes sustained the rhythm repetition of the former 4 activity periods. The properties of the “closing door” earthquakes include time and spatial clustering as well as earthquake swarm, seismic gap and banded orderly distribution image. The 7 earthauakes of MS≥5.0 in 2013 may be the “end” earthquakes of the fifth activity period.

Remote Sensing Data Dissemination System for Earthquake Emergency Based on OpenGIS and Digital Earth Platform GUO Jian-xing, WANG Xiao-qing, DOU Ai-xia, YUAN Xiao-xiang, ZHANG Wei EARTHQUAKE    2013, 33 (2): 123-131.   Abstract （95）      PDF（pc） （4367KB）（235）       Knowledge map    After a devastating earthquake occurs, damage extraction and loss evaluation from the remote sensing image data in the disaster area can provide an important basis for the earthquake emergency management and rescue mission. However, the remote sensing images must go through complex mapping, transmission, print works, before they are applied to the emergency headquarter. Digital earth platform is not only convenient, but can provide rich information to users. This paper provides a solution to build a system to share the remote sensing images acquired in the disaster area. The system is built with the open source digital earth platform and open source WebGIS server which follows the OpenGIS specification. It has successfully published the post-earthquake remote sensing images in the disaster area of 2011 Yiliang-Zhaotong, Yunan earthquake on the Web and display them in three-dimensional style with the digital earth platform,the example significantly improves the effect of displaying of the remote sensing images.

Detecting Seismic Wave Clock Drifts in Temporary Seismic Stations with Ambient Noise Cross-correlation KOU Hua-dong, WANG Wei-jun, PENG Fei, YAN Kun EARTHQUAKE    2020, 40 (4): 103-114.   DOI: 10.12196/j.issn.1000-3274.2020.04.008 Abstract （243）      PDF（pc） （4562KB）（298）       Knowledge map    Clock accuracy is one of the most important parameters in seismic observation, which is usually guaranteed by satellite timing signal. When the satellite signal is shielded or the time-keeping components of the instrument have problems, the internal clock of seismometer will drift gradually, which brings great affect to the data processing. The empirical Green's function extracted from cross-correlation of seismic background noise stations can not only be used for structural imaging, but also can be used to detect whether the waveform clock has drift and how many times drifted. In this paper, the cross-correlation monitoring method of seismic background noise is used to detect the clock drift of four mobile stations in Yongsheng area of Yunnan Province from 2017 to 2019. The results show that some mobile stations have different clock drift modes in different time periods, and the maximum amplitude can reach 1.75 s. Furthermore, the above results are verified by using the repeated signals from the Fixed Airgun Signal Transmission Stations (FASTS) of Binchuan in Yunnan province. It is found that the two results have a good consistency. Our research shows that the cross correlation of background noise has a high sensitivity to the clock drift of seismic waveform, which can effectively detect the clock problem of waveform, prevent the waveform from being misused, and provide reference information for the subsequent clock correction of waveform.

Monitoring Crustal Media Variation in Yangjiang Area of Guangdong Provinces by Using Repeated Earthquakes YE Xiu-wei, WEN Ze-gang, LIU Jin, YANG Ma-ling, HU Xin-min EARTHQUAKE    2008, 28 (4): 103-111.   Abstract （73）      PDF（pc） （1923KB）（297）       Knowledge map    In this paper the authors normalized the position of repeated earthquakes by using ray tracing, in order to improve the accuracy of seismic wave travel time to measure crustal media variation with time. The author also calculated the travel time of Yangjiang repeated earthquakes (ML≥2.0)from Jonuary 2002 to september 2007 by using ray tracing. The results indicate the short-term velocity variation of crustal media appears before Yangjiang M=4.9 earthquake in 2004.

Earthquake Direct Economic Loss of Lifeline Engineering based on Sub-area Classification ZHANG Gui-xin,SUN Bai-tao,CHEN Xiang-zhao EARTHQUAKE    2017, 37 (4): 69-79.   Abstract （259）      PDF（pc） （1401KB）（721）       Knowledge map    Eearthquake damage and loss assessment of lifeline engineering have an extremely important significance on earthquake damage defense and earthquake emergency responses. Lifeline engineering is a complex and vast network system, and until now, the existing research on earthquake damage and loss assessment of lifeline engineering shows some limitations and uncertainties. We utilized the earthquake damages and loss assessment of extensively and systematically researched buildings, and analyzed earthquake damages to buildings and lifelines in previous typical earthquakes. By integrating losses of buildings and lifelines, we established the correlation model by analyzing the quantitative relation between losses of buildings and lifeline engineering. Moreover, by analyzing kilometer grid data including population, GDP and land utilization, we defined sub-area classification principle in mainland China, and then, built the model for analyzing direct economic loss of lifeline engineering base on the principle. Furthermore, we developed the analysis module for direct economic loss of lifeline engineering based on GIS software platform, and took advantage of the module to display the spatial distribution of direct economic loss of lifeline engineering under different seismic intensities in Sichuan Province, China.

Enhancement of Seismicity Recorded by the Qiaojia Seismic Network before the 2013 Lushan and 2014 Ludian Earthquakes LI Yan-e,CHEN Li-juan,CHEN Xue-zhong EARTHQUAKE    2017, 37 (3): 95-106.   Abstract （161）      PDF（pc） （944KB）（300）       Knowledge map    A seismic network (Qiaojia network) of Twenty four seismometers operated by Institute of Geophysics, China Earthquake Administration was situated along the Zemuhe fault and the north end of Xiaojiang fault where is a part of the east boundary of the Chuan-Dian rhombus crust mass. Since the end of Feb., 2012 when Qiaojia network started to operate, the 20 April, 2013 Lushan MS7.0 earthquake and the 3 Agust, 2014 Ludian MS6.5 earthquake have occurred in the vicinity of Qiaojia network. The earthquake catalogue recorded by Qiaojia network since March, 2012 is used in this study. The temporal variation of earthquake count before the Lushan event and the Ludian event is analysed. The results are as follows: ① A very clear gradually increasing variation of the count of M 2.0 earthquakes within the region where all earthquakes recorded by the Qiaojia network coverage can be found before the Lushan event and the Ludian event, and the increasing range and duration of the count before the Ludian event are both larger than those before the Lushan event. ② In the region covered by Qiaojia network, for earthquakes with depth h 10 km a rising process of the count was manifest before both events, along with a nearly same duration of about five and a half manths, and for earthquakes with depth h>10 km a rising-dropping process of the count was manifest before the Lushan event before which the rising-dropping process showed again. The variation of the count for earthquakes with depth h 10 km is reverse to that for earthquakes with depth h>10 km; ③ Within and very close to the region covered by the Qiaojia network, the variation of the count manifests a rising process for earthquakes with depth h 10 km or h>10 km before the Lushan event and only for earthquakes with depth h 10 km before the Ludian event. The variation of the count manifests a weakening process for earthquakes with depth h>10 km before the Lushan event. It can be shown from above results that the seismicity within and very close to the region covered by the Qiaojia network showed a steeply rising change before both the Lushan event and the Ludian event. This phenomenon could be revelatory to understanding the process of earthquake development.

Seismogenic Structure and Seismic Activity Analysis of Minshan Block WAN Sen-lin, ZHANG Jun-long, LIU Ming-jun, HE Wei-Min, LI Hai-long, GUO Chang-bao, LI Zhi-min EARTHQUAKE    2020, 40 (2): 49-70.   DOI: 10.12196/j.issn.1000-3274.2020.02.004 Abstract （376）      PDF（pc） （4438KB）（411）       Knowledge map    The Minshan block is located in the middle of South-North Seismic Structural Belt in China with complex regional geological structures, numerous active faults and frequent strong earthquakes. Maowen fault, Tazang fault, Minjiang fault and Huya fault are the main active faults in different directions constitute the boundary of the Minshan block. From 638 to 2017, 11 powerful earthquakes of magnitude 6 or above occurred in this region, and the 2017 Jiuzhaigou MS7.0 earthquake is one of them. Based on the regional tectonic background, this paper summarizes the structural characteristics and seismicity characteristics of strong earthquakes occurring in Minshan block.and comprehensively analyses the seismogeological characteristics and seismic hazards in this area. It is concluded that: ① The spatial distribution of earthquakes is characterized by obvious zoning, the most destructive strong earthquake generating structures are the East-West boundary fault areas of Minshan block with strong activity, and the epicenter is located at the intersection or cutting position of two or more groups of active fault structures. ② the temporal distribution of earthquakes is characterized by migration and return and in-situ recurrence with the development of time. ③ The occurrence of destructive earthquakes along the East-West boundary of Minshan block has a certain time correlation. The seismic sequence of Huya fault in the east boundary from 1973 to 2017 is the seismic structural response of Minjiang fault in the west boundary from 1933 to 1960 about 40 years later. ④ Minshan block should be the potential danger area of strong earthquake in the future, and the potential dangerous area of strong earthquakes in the north-central section of Minjiang fault is the area worthy of further study in the near future.

Detection of Ionospheric TEC anomalies based on Prophet Time-series Forecasting Model ZHAI Du-lin, ZHANG Xue-min, XIONG Pan, SONG Rui EARTHQUAKE    2019, 39 (2): 46-62.   Abstract （353）      PDF（pc） （3354KB）（510）       Knowledge map    This paper proposed a new method for identification of ionospheric TEC anomalies using prophet forecasting model based on Facebook. First, we compared the precision of this new method with the traditional time series forecasting method (Autoregressive Integrated Moving Average, ARIMA models) and the identification method of the classical ionospheric TEC anomalies (Inter Quartile Range, IQR method), in predicting the background values of ionospheric TEC modeling. The results show that the precision of the former is obviously better than the latter two methods: about 2.55 times higher than that of the ARIMA models, and about 10.74 times higher than that of the IQR method. Meanwhile, when the best prediction modeling interval is established, the comparison of precision values is RMSEIQR=10.5841>RMSEARIMA=3.2780>RMSEProphet=0.846, indicating that the traditional detection methods have insufficiency in predicting modeling background values. Second, taking the August 8, 2017 Jiuzhaigou earthquake as example, we analyzed its ionosphere TEC anomalies and proved the effectiveness and accuracy of the new method. The results show that obvious ionosphere TEC negative anomalies appeared on the 10th and 2nd days before the earthquake, and obvious ionosphere TEC positive anomalies occurred on the 7th day before the earthquake. In addition, the comparative experiments show that the validity and accuracy of the Prophet forecasting model is significantly better than the IQR method

Analysis of Electromagnetic Disturbance Anomaly prior to the 2017 MS7.0 Jiuzhaigou Earthquake HUANG Ji-pan, WANG Xin-an, YONG Shan-shan, WANG Mo, LIU Zhong EARTHQUAKE    2019, 39 (3): 84-94.   Abstract （305）      PDF（pc） （5075KB）（397）       Knowledge map    Electromagnetic disturbance phenomena before earthquakes have been observed for many times, however the correlation should be further studied. We designed a multi-component seismic monitoring system-AETA, to monitor the electromagnetic disturbance. At present more than 200 AETA devices have been deployed in China under the support of the Chinese Earthquake Administration. On August 8, 2017, a large MS7.0 earthquake occurred in Jiuzhaigou county of Sichuan Province, China. There are 22 sets of devices installed at seismic stations within the 500 km range of the epicenter. We analyzed the observation data of 30 days before and after the earthquake using the sliding interquartile method and a 27-day window. The result shows that abnormal signal appeared at 11 stations. Among them, 4 out of 6 stations within 200 km around the epicenter have anomalies. And the positive anomaly is much more than the negative anomaly. Besides, most anomalies occurred during night time (20:00~6:00).

Geomorphic Index and Activity Characteristics of the Mid-Segment of Jiali Fault HUANG Feng, XIONG Ren-wei, LIN Jing-dong, ZHAO Zheng, YANG Pan-xin EARTHQUAKE    2024, 44 (1): 1-18.   DOI: 10.12196/j.issn.1000-3274.2024.01.001 Abstract （53）      PDF（pc） （8413KB）（75）       Knowledge map    435 tributary basin standardised steepness indices (ks), 43 tributary valley width-height ratio (VF), 55 basin Area-elevation integral index (HI), 10 tributary channel longitudinal profiles and knick points were extracted by using 30 m resolution SRTM DEM data for the middle section of the Jiali Fracture Zone (Niwuxiang-Guxiang). Based on the river steepness indices of different reaches and the distribution characteristics of a series of rift points along the river longitudinal profile, the study area was divided into three areas for comparative analysis: upstream, the south side and the north side of the lower part. The upstream ks and HI were lower than the downstream values, while the VF values were higher than the downstream values. The study results indicated that the tectonic uplift activity in the downstream area of the middle section of the fault was strong, while the uplift in the upstream area was relatively weak. Five tributaries from the north and south were selected respectively for analysis in the downstream part of the Niwuxiang-Guxiang section, and the remote sensing interpretation results showed that the fracture spreads roughly along the southern side of the river valley, and was mostly in the same position as the development of low elevation rift points of the first-order tributaries on the southern side. Combining with the results of the field fracture profile survey and dating result, the analysis suggested that the middle section of the fracture was of early Holocene or late Pleistocene age, and was accompanied by significant recoil extrusion in addition to right-slip activity. The reason was that the middle section of the fault was located directly north of the eastern tectonic junction of the Qinghai-Xizang Plateau, and it was assumed that in addition to the eastward transport of the Qiangtang block, the recoil is the result of the continuous northward pushing of the tectonic junction.

Temporal and Spatial Variations of Apparent Stress in Shandong Province, China LI Yan-e, CHEN Li-juan, WANG Sheng-wen, GUO Xiang-yun, CHEN Xue-zhong EARTHQUAKE    2015, 35 (2): 80-90.   Abstract （123）      PDF（pc） （4825KB）（345）       Knowledge map    In this paper, by using the waveform data of medium and small earthquakes in Shandong province, we calculated the earthquake energy, seismic moment and apparent stress of 206 ML≥2.0 earthquakes from January 2001 to July 2011 based on Brune model. The scaling relations of source parameters turns out that apparent stress increase with the seismic moment, except the earthquakes with ML≤2.8 from September 2008 to March 2011 during which time the apparent stress was low. The temporal and spatial variation of apparent stress shows that the stress level in Shandong province obviously increased from 2004 to 2007, and the high value concentrated in Anqu—Changyi, Juxian—Tancheng, Liaocheng—Lankao,and jiaodong peninsula, the stress remained low after 2009 and began to rise from March 2011, which deserves continous concern.

Object-oriented Detection of Earthquake Building Damages LIU Ming-zhong, LI Cheng-long EARTHQUAKE    2013, 33 (2): 109-114.   Abstract （111）      PDF（pc） （3329KB）（215）       Knowledge map    Change detection from remote sensing image is an effective method to estimate earthquake damage. With the improvement of of spaceborne image resolution, single pixel is gradually replaced by object as the basic unit for change detection. The principle of object-oriented change detection method is described in this paper. And then data processing flow is stated. Taking high-resolution remote sensing images pre- and post- the 2010 Yushu earthquake as an example, the accuracy of this method to extract building damage is shown. This method is compared with direct change detection method based on pixel, and based on principal component analysis. The results show object-oriented change detection method has the highest accuracy in building damage estimation.

Neural networks of radial basis function (RBF) and it′s application to earthquake prediction WANG Wei, WU Geng-feng, ZHANG Bo-feng, WANG Yuan EARTHQUAKE    2005, 25 (2): 19-25.   Abstract （230）      PDF（pc） （89KB）（418）       Knowledge map    the principle and algorithm of neural networks of Radial Basis Function (R BF) and its application to the expert system for earthquake prediction (ESEP 3.0) are introduced in this paper. The actual application in earthquake forecast shows that the neutral networks can overcome some demerit of BP neural networks in leaning process, the constringency excessively depend on initial value and optimization constringency and often can′t appear. The RBF neural networks possess the rapid operation speed in learning and strong nonlinear mapping ability and very good efficiency.

Study on Correlation Coefficient of Spectral Amplitude of Gaizhou Earthquake Swarms YANG Shi-chao, ZHANG Bo, CAO Feng-juan, WANG Liang, SHAO Yuan-yuan EARTHQUAKE    2019, 39 (3): 158-165.   Abstract （274）      PDF（pc） （2756KB）（437）       Knowledge map    The spectral amplitude correlation coefficient of the 2012 Qingshiling earthquake swarm and the 2014 Xihaiyu earthquake swarm in Gaizhou City were calculated by using digital seismic waveform data recorded in Liaoning Digital Seismic Network. The results show that the correlation coefficient of spectral amplitude of Qingshiling earthquake swarm is 0.72~0.90 and finally stabilizes at 0.75. The low value of the correlation coefficient of spectral amplitude indicates low consistency of focal mechanisms. The correlation coefficient of spectral amplitude of Xihaiyu earthquake swarm is 0.85~0.99 and finally stabilizes at 0.85. The high value of the correlation coefficient of spectral amplitude indicates high consistency of focal mechanisms. According to the analysis of the apparent stress in Gaizhou City, it is deemed that the variation of correlation coefficient of spectral amplitude of Gaizhou City is related to the change of stress level in this region.

The focal mechanism determinations of moderate-small earthquakes using the first motion and amplitude ratio of P and S wave LIU Jie, ZHENG Si-hua, KANG Ying, CHOU Yong-qing EARTHQUAKE    2004, 24 (1): 19-26.   Abstract （121）      PDF（pc） （1651KB）（263）       Knowledge map    The focal mechanisms of moderate-small earthquakes are calculated tentatively using digital seismic wave data in some provincial digital seismic networks based on the program of focal mechanism determinations combing the first motion of P, SV and SH waves with their amplitude ratio, which is recently developed by Snoke. Some results are compared with the results obtained by P first motion data. It shows that the method is feasible, and it provides a new possibility using digital seismic data in earthquake prediction.

Analysis on the characteristics of Ninghe earthquake sequence occurred in 2003 WANG Jun-guo, YAO Lan-yu, BIAN Zhen-fu, LI Wen-dong, WU Xiao-zhi, HE Qiao-yun, PANG Qun-ying EARTHQUAKE    2004, 24 (2): 103-108.   Abstract （64）      PDF（pc） （1088KB）（328）       Knowledge map    Ninghe earthquake sequence occurred in April of 2003 was clearly felt by the majority area of Tianjin municipality and the epicentral intensity is V. The analytical results indicate that Ninghe earthquake sequence has the basic characteristics of earthquake swarm in the distribution of space, time and intensity. However, it is different from the traditional earthquake swarm because it had only a few aftershocks and its frequency and intensity attenuated rapidly. Although Ninghe earthquake sequence occurred at the southwestern end of Tangshan aftershock zone, it has the spatial characteristics of its own. The focal-mechanism solutions of three M≈4 earthquakes are not consistent, which might be related to the complicated tectonics in the focal region. It is a kind of manifestation of the stress adjustment and variation in the focal region, indicating that the stress in the focal region is still being adjusted.

Seismogenic Fault of the 1303 Hongtong M8 Earthquake in Shanxi Province QI Yu-yan,LU Guo-jun,SUN Li-na,FANG Sheng-ming,WANG Xiao-shan,FENG Xiang-dong,DIAO Gui-ling EARTHQUAKE    2017, 37 (1): 148-157.   Abstract （299）      PDF（pc） （1028KB）（440）       Knowledge map    The great Hongtong M8 earthquake occurred in 1303 in Shanxi Province,was the earliest M8 earthquake in China, according to historical records. Though the earthquake has a history of more than 700 years, small earthquakes have been continually occurring till now. This study determines the fault geometry of this earthquake by inverting seismological data of present-day moderate-small earthquakes in the focal area. We select a strip-shaped zone from the relocated earthquake catalog in the period from 1981 to 2013 to invert fault plane parameters of this earthquake. The inversion results of the Hongtong M8 earthquake are as follows: the strike is 19.3°, the dip angle is 88.5°, the slip angle is -170.0°, the fault length is about 75.5 km, the fault width is about 26.2 km, the lower-boundary depth is about 37.35 km and the buried depth of upper boundary is about 11.12 km. The relocated earthquakes are divided into two parts by the Hongtong fault. The earthquakes which located in the north of Hongtong fault are named as the north part, and the earthquakes which located in the south of Hongtong fault are named as the south part. We invert fault plane parameters for the two parts, the inversion results of the north part are as follows: the strike is 13.7°, the dip angle is 76.6°, the slip angle is -157.6°, the fault length is about 32.7 km, the fault width is about 21.7 km, the lower-boundary depth is about 32.86 km and the buried depth of upper boundary is about 11.97 km; the inversion results of the south part are as follows: the strike is 20.3°, the dip angle is 87.1°, the slip angle is -154.6°, the fault length is about 45.9 km, the fault width is about 16.6km, the lower-boundary depth is about 25.50 km and the buried depth of upper boundary is about 9.32 km. It shows that the seismogenic fault is a right lateral strike-slip fault. The seismogenic fault depth of the north part is deeper than the south one. The seismogenic fault depth and its dip of the north part are similar to the results of the speculative conclusion by deep seismic exploration. The projection of the seismogenic fault on the ground corresponds well with the high intensity region of the Hongtong earthquake.

Study on the Spatio-temporal Evolution Characteristics and Seismic Structure Environment of the 2019 M6.0 Changning Sichuan Earthquake Sequence GONG Yue, WANG Yu-xi, LIANG Ming-jian, LONG Feng, ZHAO Min EARTHQUAKE    2020, 40 (4): 90-102.   DOI: 10.12196/j.issn.1000-3274.2020.04.007 Abstract （220）      PDF（pc） （4852KB）（493）       Knowledge map    Features of seismic sequence can directly reflect the differences among tectonic stress field, seismotectonic and seismogenic environment. For example, mainshock-aftershock-type earthquakes mostly occur in a relatively uniform medium environment. However, foreshock-mainshock-aftershock-type earthquakes and swarms mainly occur in complex structure. On 17 June, 2019, the M6.0 an earthquake occurred in Changning County, Yibin City, Sichuan Province. Its aftershock totally distributed along a NW direction belt, bit in the northwest part of the belt, the aftershock distribution showed the cluster features. There is an obvious difference between the southeast part and northwestern part for aftershock activity. The southeast part can be considered as a mainshock-aftershock type with a fast decay. The northwestern part shows a feature of swarm, which decay is slowly and many aftershocks with M5 or more in the early stage. The M6.0 earthquake occurred in the Changning-Shuanghe anticline which is complicated and composed of several secondary fold structures and associated faults. The segmentation characteristics of the Changning M6.0 earthquake indicate that it is hardly to be produced by a single fault but a cascade fractures. Moreover, the aftershock focal depths in the northwestern part are more deeply, this means that the seismic activity in this area has been controlled by the Huaying Shan fault zone. Oppositely, the possible influence of the 2019 Changning M6.0 earthquake on Huaying Shan fault zone should be emphasized in the future.

Migration-earthquake after the 2020 Yutian MS6.4 Earthquake, Xinjiang ZHANG Jun-long, MU Ruo-yu EARTHQUAKE    2021, 41 (2): 47-61.   DOI: 10.12196/j.issn.1000-3274.2021.02.004 Abstract （204）      PDF（pc） （3404KB）（203）       Knowledge map    Based on the review of the anomalies before the 2020 MS6.4 earthquake in Yutian and the sequence of strong migration- earthquakes in recent years, the seismogenic structure and dynamic of the Yutian earthquakes are analyzed. The temporal and spatial distribution of the “initiation-earthquake to migration-earthquake” in the future are discussed. According to the phenomenon of special earthquake migration and regularity in large space scale, based on the review of the pre earthquake anomalies of Yutian MS6.4 earthquake in 2020 and the sequence of originating earthquake-migrating earthquake in Yutian region since 1900, the seismogenic structure and dynamic background of Yutian earthquake are analyzed, and the temporal and spatial distribution and trend of originating earthquake-migrating earthquake in Yutian region are discussed. This paper focuses on the statistics of earthquake migration phenomena (such as migration direction and time interval) in Yutian area in recent years. The statistical results support that earthquake migration can be used as one of the methods for medium and long-term seismic risk analysis in this area, and try to apply it to the analysis of future earthquake migration trend. The cause and dynamic mechanism of earthquake migration need to be further studied.

Optical Fiber Sensory Technology: Future Direction for Earthquake Precursor Monitoring LIU Wen-yi, ZHANG Wen-tao, LI Li, HUANG Wen-zhu, LI Fang EARTHQUAKE    2012, 32 (4): 92-102.   Abstract （187）      PDF（pc） （1822KB）（488）       Knowledge map    Optical fiber sensor is a novel method for earthquake precursor monitoring with many advantages, such as high-precision, anti-electromagnetic interference, no zero drift, the simplicity of establishing network and the flexibility of implementing long distance transmission. Optical fiber sensor can solve the intrinsic defect of electrical measuring instrument for detecting earthquake precursor. The sensing principle and characteristics of several kind of common optical fiber sensor is introduced. The research progress of optical fiber sensor in the applications of the crustal deformation observation and seismic wave detection is summarized. And the existing problems need to be solved is proposed. We developed a set of comprehensive drilling earthquake observation equipment based on optical fiber sensor, which can detect crustal deformation, seismic wave and earth temperature. Field experiments show that the optical fiber comprehensive drilling earthquake observation equipment adapts to the performance requirements of resistance to environmental interference ability, measurement accuracy, stability and so on, and have good application prospects.

An Improved Technology for Estimating Seismic Influence Field based on Levenberg-Marquardt Method YANG Yan-ming,JIANG Li-xin,WANG Zhen-xiang EARTHQUAKE    2017, 37 (3): 117-126.   Abstract （236）      PDF（pc） （561KB）（450）       Knowledge map    Attenuation relation of seismic intensity is fitted by using 152 complete isoseismic lines from 65 earthquakes greater than MS4.0 from 1940 to 2015 in Inner Mongolia and neighbouring areas. Meanwhile, based on the difference of land form and geological structure characteristic,the areas are divided into eastern regions, western regions and the central regions. And then, intensity attenuation relationships are established separately by using Levenberg-Marquardt method and elliptic attenuation model. Comparisons are made between the respected earthquake influence field model of North China and computed results. The result shows that the relation obtained well represents the features of earthquake damage distribution in the areas, and has positively meaning to guiding the loss assessment immediately after a desastrous earthquake.

Monitoring Media V elocity Variations with Coda Wave Interferometry ZHANG Jin-chuan, WANG Qin-cai, XUE Bing, Ding Li-sha EARTHQUAKE    2014, 34 (3): 62-73.   Abstract （140）      PDF（pc） （576KB）（391）       Knowledge map    Multiply scattered waves are sensitive to media changes owing to the effect of re-peated sampling, superposition and amplification. Based on this characteristic, small medi-um changes could be detected by using coda wave interferometry. In recent years, coda wave interferometry is widely used in estimating velocity variation with high precision in areas such as seismology and non-destructive testing. This paper systematically presents the principle, method and research status of coda wave interferometry respectively, especially focusing on research advances of media velocity variations by using repeating earth-quake,artificial source, and ambient seismic noise. Applications of coda wave interferome try can contribute to the more subtle understanding of dynamic evolution process in the medium.

Study on the Relation between Isoseismic Line, Aftershock Area of Strong Earthquakes and their Seismotectonic Environments HAN Wei-bin, JIANG Guo-fang EARTHQUAKE    2010, 30 (4): 32-39.   Abstract （81）      PDF（pc） （355KB）（225）       Knowledge map    In this paper, isoseismic lines, aftershock areas of strong earthquakes in Sichuan-Yunnan area and North China with their Seismotectonic environment have been compared and studied. The main results are: ① Both the rates between the length and the width of isoseismic lines, and the lengths of aftershock area of strong earthquakes are related to the lengths of their seismogenic faults, and are related to their magnitudes too. ② The rates between the length and the width of isoseismic lines of strong earthquakes are also influenced by overburden in the region, but the lengths of aftershock area of strong earthquakes are not influenced by overburden in the region, maybe the latter can mainly reflect distribution of the seismogenic fault and nearby deep small faults.

Study on neotectonic characteristics and its evolution in northwestern Hainan Island ZHANG Jun-long, TIAN Qin-jian, LI Feng GAO, Zhan-wu, SU Gang EARTHQUAKE    2008, 28 (3): 85-94.   Abstract （99）      PDF（pc） （2083KB）（227）       Knowledge map    The terraces in western Hainan Island have been measured by using DGPS system. Based on their geomorphic feature, two type terraces are divided. One is marine landform including a sand bank and four terraces. The sand bank is 10 meters high and formed since 5000a. The first terrace is 20 meters high and formed nearly in Holocene. The second terrace is 32~34 meters high and formed in late Pleistocene. The third terrace is 40~42 meters high and formed since nearly 121.8 ka. The fourth terrace is 57~62 meters high and only occurred in a few counties and formed in late mid-Pleistocene. The other is fluvial landform, including four terraces. The first terrace is 20 meters high and formed since 11.4 ka. The second terrace is 34 meters high and formed since 47.2ka. The third terrace is 50 meters high, but the elevation of surface of terrace base is 41 meters, which formed in the early stage of late Pleistocene. The fourth terrace is 71 meters high, but the elevation of surface of terrace base is 60 meters, which formed in the late stage of middle Pleistocene. The second terrace is well developed. Since Late Pleistocene, the whole region accelerates uplifting. Furthermore, the activity of Wangwu-Wengjiao fault may be weaker.

STUDY ON FEATURES OF EARTHQUAKE SEQUENCES IN EAST CHINA Huang Yun, Zheng Jiangrong EARTHQUAKE    1999, 19 (2): 190-198.   Abstract （44）      PDF（pc） （92KB）（268）       Knowledge map    A systematic analysis of earthquake sequences of magnitudes MS ≥ 5. 0 in East China since 1970 shows that four types of earthquake sequences might be distinguished, i.e., the single type, the apparent single type-this is essentially a mainshock-aftershock type, which is to acestain extent similar to the single type, the mainshock-aftershock type and the swarm type, according to the magnitude difference between the largest and second largest earthquakes. Rather satisfactory results have been obtained in the investigation on the early determination of sequence type using that aftershock samples recorded during the periods of 0.5, 1, 2, 3, 5 and 7 days respectively after the mainshock. An attempt has been made to analyze the duration of aftershocks using a new method. Assuming a back-g round seismicity for a given area, the aftershock activity is considered to come to the end (on the whole), when the aftershock activity attenuates to this background value. The features of duration of aftershock sequences in the East China are discussed and the strength and frequencies of strong aftershocks are analysed using this method. Features of variations of the characteristic parametersb and for different type aftershock sequences are analysed. The features of the aftershock activity in this region discussed above can provide a scientific basis for accurate determination of seismicity trend that follows a major earthquake in the East China.

Temporal-spatial Variations of Focal Dynamic Parameters in the Capital Circle and Surrounding Areas before the 2006 Wen'an MS5.1 Earthquake in Hebei Province Chen Xue-zhong, Li Yan'e, Guo Xiang-yun EARTHQUAKE    2011, 31 (4): 15-25.   Abstract （53）      PDF（pc） （2783KB）（162）       Knowledge map    Based on near-source conditions, we used waveform data observed by the Beijing Digital Telemetry Seismic Network and obtained source spectrum, corner frequency and zero frequency amplitude values of 989 earthquakes with magnitude larger than ML2.0 occurred in the capital circle of China and surrounding area from January 2002 to June 2006 by the Brune model. Some relevant formulas had been used for calculation of a few focal dynamic parameters, such as rupture radius, seismic moment, seismic energy, stress drop, apparent stress, and so on. The scaling relations of these dynamic parameters and characters of the temporal-spatial variations before the Wen'an MS5.1 earthquake in Hebei Province of July 20, 2006 had been analyzed. Results show that apparent stress, stress drop, seismic energy and rupture radius ratio appeared relatively high in some focus areas before the Wen'an MS5.1 earthquake. These areas were mainly distributed in the North China Plain. It could be seen from the time curves that apparent stress, stress drop, seismic energy and rupture radius ratio and other parameters had shown a significant increasing process before the Wen'an MS5.1 earthquake, but corner frequency showed a trend of decreased variation. This result might be related to the increasing process of stress in the North China Plain before the Wen'an MS5.1 earthquake.

Review on the application of statistics in seismicity CHEN Shi-jun, MA Li EARTHQUAKE    2002, 22 (1): 32-42.   Abstract （63）      PDF（pc） （126KB）（204）       Knowledge map    In this paper, we concisely retrospect somerecent progress and importantre-search results on the application of statistics in seismicity. Relevant re searches and devel-oping tendency on the attenuation of frequency versus time of after shocks, relation of magnitude-frequency and the development of stochasticsimulation on seismic process have been mainly introduced and discussed.

The Study on Early Sequence Parameters and Probability Forecasting of Strong Aftershocks of Changning MS6.0 Earthquake on June 17, 2019, Sichuan Province BI Jin-meng, JIANG Chang-sheng, MA Yong EARTHQUAKE    2020, 40 (2): 140-154.   DOI: 10.12196/j.issn.1000-3274.2020.02.011 Abstract （224）      PDF（pc） （3559KB）（385）       Knowledge map    An MS6.0 earthquake occurred on June 17, 2019 in Changning, Sichuan Province, which was followed by a series of strong aftershocks. In order to better analyze the sequence characteristics and predictability of the strong aftershocks, this paper focuses on the comparative study of the applicability of the “Epidemic Type Aftershock Sequence” (ETAS) model which have been widely adopted internationally for complex sequence, the Omi-R-J model which based on the Reseanberg-Jones (R-J) model. We compare the stability of model parameters, forecasting results by continuous sliding, fitting and aftershock occurrence rate forecasting, and evaluate the effectiveness of forecasting by using the N-test and T-test with multiple time windows. The results show that the sequence parameters αETAS of response excitation ability of Changning MS6.0 earthquake sequence is obviously smaller than other parameters of moderate-strong earthquake sequence, while the pORJ value of response attenuation ability and the bORJ value of response stress accumulation level are relatively small, which are consistent with the rich and relatively long duration of this aftershock sequence. ETAS and Omi-R-J models still have certain forecasting ability for strong aftershocks of complex sequence at three magnitude ranges [3.0, 3.5, 4.0]. The overall “Information Gain Per Earthquake” (IGPE) calculation results show that the ETAS model is slightly superior to the Omi-R-J model, thus the former is more suitable for aftershock forecasting of complex earthquake sequences.

An Issue on Coulomb Static Stress Triggering Study: Applied to the 2012 Yushu Earthquake CAO Jian-ling, ZHANG Jing, WANG Hui EARTHQUAKE    2012, 32 (4): 83-91.   Abstract （62）      PDF（pc） （2992KB）（238）       Knowledge map    Static stress change has been widely used since the concept of earthquake triggering was proposed. Corresponding effect of Coulomb failure stress of major earthquake and its aftershocks is influenced by many factors. Among them, fault slips at different depths lead to differences of the static Coulomb stress image at depth. To select the stress image at what depth to discuss the trend of subsequent earthquakes is an important issue. This paper presents a calculation method: Firstly, we calculate static Coulomb stresses at various depths, and then take the highest stress value at different depths at the same location to draw the static stress image. We take the 2010 Yushu earthquake for an example to assess the effect of the calculation method proposed in this paper combined with the seismic activity and the static Coulomb stress distribution. The results show that, in the two years after Yushu earthquake, the aftershock with magnitude larger than 3.0 occurred almost always in the Coulomb stress increase area, using two rupture models given by different researchers.

Dynamic Variations of the Horizontal Deformation Field in North China ZHANG Feng-shuang, YANG Bo, ZHAN Wei EARTHQUAKE    2011, 31 (1): 75-85.   Abstract （45）      PDF（pc） （3013KB）（193）       Knowledge map    In order to grasp the space-time variation of regional strain field holistically, and to describe the regional movement field more objectively, on the basis of region with no-net-rotate datum and from the point of continuous variation, we applies multi-kernel function in filtering the repeated measurements from GPS monitoring stations in north China during the recent 10 years (1999, 2001, 2004, 2007 and 2009) in the project of China Crust Movement Measuring Network, and analyzes the dynamic variation fields. The results suggest: ① Beijing and Tianjin and their surrounding regions located in Zhang-Bo Zone are the differential motion area compared with their neighborhood, and also are depletion areas of left lateral movement,and have lasted for a long time; ② The north segment of Shan Xi fault is left lateral compressive activities and south of it is right lateral compressive, which is not completely consistent with the geological result of right lateral extension; ③ The activity of Tanlu fault is left and right lateral alternation on space, and is not totally right lateral, and in term of fault extension, this fault is ‘compressive in north and extensive in south’; ④ The region between south of Taiyuan-Shijiazhuang and north of Jinan is the obvious deformation region during the recent years.

Structure and design of emergency command system in earthquake site JIANG Li-xin, WU Tian-an, LIU Zai-tao, ZHANG Jian-fu, JIANG Long EARTHQUAKE    2004, 24 (3): 35-41.   Abstract （67）      PDF（pc） （976KB）（200）       Knowledge map    The emergency command in earthquake site is an important part of earthquake disaster mitigation, getting and transmitting all kinds of information in earthquake site are main contents of it, and the data about the disaster situation are significant foundation for the government to arrive at a decision of it. During “the Tenth Five-Year-Plan”, the emergency command technical system in earthquake site will be built up. Presently, it is at an early stage that the researching and building on this aspect in our country, and there are still lots of problem need to be investigated and discussed deeper. In this paper, according to the building process of “the Ninth five-Year-plan”, the system structure of this technical system is dissertated, preliminary design project and technical framework are presented, and the future development is discussed.