LI?Jian-biao , GAN?Wei-jun , RAN?Yong-kang , CHEN?Li-chun
2006, 28(2):97-103.
Abstract:Based on the analyses of active faults and Global Position System (GPS) data of the eastern Tibet plateau, the paper attempts to discuss the geometry, kinematics and deformation of the active blocks in eastern Tibet plateau. The preliminary conclusions are: (1) The boundaries of the "active" blocks which have actived in Quaternary, especially in Late Pleistocene are associated with the primary boundaries of the tectonic units (those are five suture zones and a deep, lithospheric fault zone between the terraines) , a few were newly formed since late Quaternary Period; (2) The kinematics characteristic of all active blocks induced from the active faults data are as same as one from GPS data, as the boundary, Xianshuihe - Yushu - Mani fault belt is very important for the movement way of the active blocks at the southern the fault belt is different from the ones at the northern side ; (3) Not only does the intensive deformation exist within the boundary zone between two active blocks, but also the deformation has taken place in the active blocks interior since Quaternary Period; (4) Since Late Pleistocene, the kinematics and deformation characteristic of the Tibet plateau crust should be that: when the active blocks moved to NE under the Indian plate compression, the steady blocks (i.e. Xiyu block region, Huabei block region, Nanhua block region) at the front held up the movement of the blocks, meanwhile the adjustment way of the active blocks was thickening crust and the blocks horizontal transfer to the tectonic weaker places, that is, the active blocks at the south of Xianshuihe - Yushu - Mani fault belt rotated clockwise to SE -SSE as an entirety around the Eastern Himalayan Syntaxis, while the blocks in the northern side of the fault belt displaced sinisterly to NWW -W.
XU?Kai-jun , LI?Tong-lin , ZHANG?Hui , LI?Jian-ping
2006, 28(2):104-107.
Abstract:Using integral equation method, the numerical algorithm of 3D magnetotelluric responses in homogeneous half-space is realized. While calculating tensor Green~ functions , the algorithm of secondary division is adopted to solve the singular problem. The Gaussian quadrature and continued fraction is adopted to calculate the integral with Bessel function. This method not only can ensure the right calculation of tensor Green's functions but also can get high precision. The correctness of algorithm has been proved by model comparing and analyse. This efficient algorithm will help to study the distributing laws of 3D magenetotelluric responses and to setup basis for reaserch of 3D inversion.
2006, 28(2):108-113.
Abstract:Based on the single scatter model( Aki ), using 37 earthquake digital wave data above ML3.0 from 2000 to now recorded by Zhejiang and Anhui earthquake nets, the average Q value of coda in relative region is calculated, and relationship between Q value and frequency is polyfited. The result isQ(f)=212±33.5f^0.62±0.11. Contrasting the result with that of other domestic region, the coda scatter feature is that the Q value is higher but dependence on frequency is lower, so it is considered that tectonic activity and seismisity are low in this region. Also the effects from those factors including coda windows length, noise level, filter type and so on, which are thought to change Q value in data processing, are analysed deeply in this paper.
LEI?Dong-ning , FAN?Guang-ming
2006, 28(2):114-117.
Abstract:Through detailed analyses for available data concerning low-velocity and high conductive layer beneath the crust and seismic depths, based on the studying of seismic precursors, characteristics and physical mechanisms, a simple double-storey seismogenic hypothesis of the crust for continental strong shocks is preliminarily presented in this paper. The upper layer in mid-upper crust is main earthquake pregnant layer where stress concentrats and strain energy releases in earthquakes events, and is a brittle deformation layer of rocks. The lower one in mid-lower crust with high conductive and low velocity of P wave, is believed that it is one of the most important factors inducing and enhancing brittle deformation, strain energy cumulation and crack in the upper rocks. The latter layer locates in a transitional zone of rock deformation from brittle to ductile, which is closely associated with the occurrence of strong shocks. Meanwhile, seismogenic environment and significance for strong shocks based on the double-storey pattern are discussed in paper.
ZHAO?Shu-li , ZHU?Yuan-qing , YU?Hai-ying , SONG?Zhi-ping
2006, 28(2):118-122.
Abstract:The establishment of the calibration database in Seismic Array of Shanghai which based on the calibration theory is introduced. Two new calibration methods, the nearest calibration and the average calibration, are presented, and the methods are tested by chosen typical earthquake events. The result shows that both methods are more available and have good calibrate result. By using new methods the location precision of earthquake for the array is improved.
LI?Ya-rong , RONG?Dai-lu , Han?Xiao-ming
2006, 28(2):123-128.
Abstract:Taking a planed reservoir dam as the example, the displacement, strain and stress in the dam area which is located near active fault in M 6 - 7 earthquake are calculated in this paper. The results show that the deformation can reach a higher values and cause serious damage to structure. So the ' antirupture problem' must be considered for the important and great engineering near active fault.
MA?Wei-yu , XU?Xiu-deng , XU?Bao-hua , ZHANG?Xing-cai , XU?Jie
2006, 28(2):129-133,158.
Abstract:The geological structure environment of Indonesia Mw 9.0 earthquake on December 26, 2004, locate at west coast of northern Sumatra, is preliminary analyzed, and the changes of the NCEP data and the additive tectonic stress from astro-tidal-triggering are retrospeutively researched. The result shows an evident temperature abnormal increase and spatial - time evolvement rule of the original temperature rise →enhancing rise→pinnacle rising→attenuation, calmness→earthquake occurrence. Both main earthquake and strong aftershocks occurred at the time that the astro-tidal-triggering reach the absolute value apex. This special earthquake proved that a new thinking to utilize the NCEP data and the astro-tidal-triggering for short-term and impending earthquake prediction is feasible.
GE?Wei-peng , YUAN?Dao-yang , GUO?Hua
2006, 28(2):134-139.
Abstract:In urban active fault surveying project, research on the spatial data modeling based on Seismogeloglogy and active tectonics is very important for interrelated application fields. According to the stipulation of Technical System for China Earthquake Active Fault Surveying, the Seismogeloglogic Data Model is studied and created using Unified Modeling Language ( UML) in this paper. It emphasizes the method of data integration about active fault surveying and the structure of Seismogeloglogic Data Model, and it also presents the class structure graphs and the relations chart of classes based on ArcGIS. Meanwhile the attributes of seismogeloglogic UML data model are analyzed.
XU?Shun-hua , WANG?Lan-min , YUAN?Zhong-xia
2006, 28(2):140-143.
Abstract:Based on the statistic data of loess seismic subsidence from the seismic micro-zoning works in Lanzhou and Baoji, many influence factors on the subsidence such as water content, void ratio, dry density and initial elastic modulus are analysed, and some more available, more concrete initial judging criterions for the loess seismic subsidence are obtained. Meanwhile the application of initial elastic modulus to the judging work is discussed.
GAO?Li-xin , CHE?Yong-tai , JI?Jian-guo , YAN?Hai-bin , WANG?Hai-yi , LIU?Cheng-long , WANG?Cui-ping , YU?Hong-mei
2006, 28(2):144-148.
Abstract:The test for the influence of the same layer pumping water to observation of water level , water temperature, escaping radon, escaping Hg, water radon, and water Hg in Gucheng village, Inner Mongolia Autonomous Region, is introduced. The test result shows that the main influence is on the underground water level, the influ evidence. The influence on Hg are not important. ence distance is about 1 km. The influence on water temperature is relatively escaping radon and Hg are not evidence. The influence on water radon and
HE?Shao-lin , LI?Zuo-tang , YAO?Zi-wen
2006, 28(2):149-153.
Abstract:The necessity, system structure, system function, technique character and application foreground for the software system of management and server to earthquake emergency database in Gansu province is introduced.
JI?Feng-ling , LI?Qiang , CHENG?Xin-ming
2006, 28(2):154-158.
Abstract:The lightweight treated soil ( LWTS ), a new type of light weight geo-material ( LGM), has advantages such as light weight, high strength and environment protection et al.. The mechanics properties of two type of the LWTS mixed with different foamed plastic beads are researched by the uniaxial compression test, the isotropic compression test and the triaxial compression test. The results show that the type of beads has greater effect on the mechanics properties of LWTS.
LI?Ying , ZHANG?Shu-zhen , XU?Kang-sheng
2006, 28(2):159-162.
Abstract:In this paper, the method of wavelet multiresolution analysis denoise is applicatied in seimic signals recorded in Lanzhou Station. The results show that signal noise ratio of seimic data increase 11.6 -55.6 dB, average 29 dB, and the original signal property is kept well. It is effective and reliable that applicats it in seismic signal denoise.:
YANG?Guo-dong , WU?Yong-xin , XU?Hui
2006, 28(2):163-166.
Abstract:Through the related analysis for the strengthing earthquake activity phenomenon and the output of coal mine in Huating region, Pingliang City, Gansu Province, from 2001, and study on the historical mineral earthquake data in China as well, the conclusion that the increased earthquake activity phenomenon is caused by mining in Huating region is taken. The earthquake developping trend and earthquake disaster in the region are predicted, and some suggestion on earthquake prevention and disaster mitigation are out forward in this paper.
ZHOU?Cui-ying , WANG?Hong-wei , ZHANG?Ji-hong , LI?Hong , XU?Ping
2006, 28(2):167-171.
Abstract:The effect of SQIP method on the medium range earthquake prediction in Northern China are reevaluated, the R values calculated by Xu grade criterion are 0.67 - 0. 68 using the retrospective all time-space scan. And the medium-short and short range prediction index of this method is also extracted. The results show that after the anomaly region of synthetical parameter P shrinking about 7 months in average, main earthquake would accure. Among them 53% -54% events accured in 6 months after the shrinking, the 33% -35% events were in 3 months, and a few of events accured after the anomaly region disappeared for 7 - 8 months. Therefore, the anomaly region of synthetical parameter P shrinking or disappearing can be the medium-short range or short range predicting index for moderate strong earthquake.
SONG?Zheng-na , SHEN?Jun , ZHAO?Chun-qing , LI?Jun , CHEN?Jian-bo , GE?Ming
2006, 28(2):172-179.
Abstract:Wanyaogou Fault is the main active fault in Urumqi city, Xinjing Uygur Autonomous Region, which had avtived in the middle period of late-Pleistocene. It is covered by the Quaternary deposits with depth of some tens meters in urban and suburban areas of Urumqi. In this paper, ultra-shallow P-wave reflection exploration for Wanyaogou Fault in northeastern suburb of Urumqi with less interference background is introduced. In the exploration, we used the methods of small geophone group interval, proper offset, short spread, multiple stacking fold and high-frequency geophones, as well as appropriate data processing method, 3 typical P-wave reflection profiles are carried out, from which the Quaternary base interface and the locations of the faults can be distinguished. The results show that in the good exploration environment, only if the proper surveillance layout is selected and the difference between the medium of both side is distinct, the uhra-shallow P-wave reflection method can be applied to detect the fault with depth of less than 50 m.
QUAN?Quan , WANG?Ling-zhen , HUANG?Cheng-min
2006, 28(2):180-183.
Abstract:Using information diffusion method, the risk on earthquake frequency and magnitude in Yunnan province is evaluated, and based on the calculate results, tactics for the management of earthquake risk are put forward.
WU?Yong-xin , ZHONG?Xin , CHEN?Lan-qing
2006, 28(2):184-188.
Abstract:Through experiment, theory analyzing and structure anatomizing, the accuracy, stability and repeatability of radon standard source which used in seismic observation stations are researched. It is found that main influence factors for the accuracy, stability and repeatability of radon standard source are tightness, leakage and block in the pipes. According to study result, some methods of maintenance in process of using are given in this paper.
2006, 28(2):189-191.
Abstract:The main study results of depth seismic sounding in the northeastern margin of Qinghai-Tibetan plateau(32°-40°N, 100°-108°E) are reviewed and summirized in this paper. The crustal structure characteristic of seismic wave velocity and the shape of the Moho in this area are given.
Sopyright:China Earthquake Engineering Journal