1989, 11(3):3-15.
Abstract:From another aspect of piezomagnetic effect-magnetization influencing stress, this paper deals with the seismomagnetie questions. Using the theories of magnetic domain and magneto-elastic coupling, obtains the elastic equilibrium equation containing magnetostrictive effect in the dimension of the earth science. From this, analyses the influence of changing magnetic field upon the stress and the mechanical features of the Curie surface. The model estimation is made for the part of magnetic contribution of the thermal stress. This anomalous stress is enough to influence the occurrence of the earthquake. Finally, from the results mentioned above, also discusses the prediction problems of some earthquakes with source model.
1989, 11(3):16-26.
Abstract:In this paper, using C. E. Shannon's information formula the author defines earthquake sequence information formula and obtains earthquake sequence information formula of the b value. Taking Menyuan aftershock sequence and other sequences for examples, practical earthquake sequence information and theoretical ones are calculated and compared each other. A result is obtained, it is H (△M)=α-βln△M and information dimension of earthquake sequence is obtained too. This paper calculates information and information dimension of foreshock and aftershock sequences of Haicheng earthquake, swarm sequences of Shenwo reservoir and Longyao, and Tangshan and Menyuan aftershock sequences. The following main results are got:
(1) Information dimension of aftershock sequences waves and reduces with time.
(2) Information dimension drops before strong earthquakes.
1989, 11(3):27-32.
Abstract:In this paper the crossing theory of stationary normal sequence is introduced briefly. Using this theory, the strong earthquake trend of three regions in our country is analysed. The three regions are Tianshan Mountain Seismic Belt, Tibet Seismic Belt and the North-South Seismie Belt in central China. A quite good result is obtained.
1989, 11(3):33-40.
Abstract:This paper puts forward a new method for computation of resistivity weighting coefficients of horizontal strata. This method is the development of the digital linear filter method for the computation apparent resistivity curve for a horizontally stratified earth. The principle of the computation method is expounded. The computation speed and precision of the new method are illustrated. Some computation results of the weighting coefficients for a three and four horizontally layered earth are shown. The variation characteristics of the weighting coefficients are analysed with emphasis on negative effect and peaking effect.
1989, 11(3):41-46.
Abstract:According to the principle of relative localization, this paper set up a method and program to measure location and original time of earthquake by using Pn phase and Quasi-Newton Optimization, and made an application to the earthquake sequence occurred in South Yellow Sea on May 21, 1984.
Zhang Zhaodong , Zheng Jinhan , Feng Chugang
1989, 11(3):47-52.
Abstract:On the basis of the solutions of partial differential equation of the effect of earth tide and barometric pressures on the well water level of confined aquifers under the condition of non-drainage, this paper analyzes the quantitative relationship between the earth tide effect of well water level and the barometric pressure effect and the parameters of confined aquifers. The paper also compares the results of the theories with the results of field observations of earth tide and barometric pressure and both are identical satisfactorily.
1989, 11(3):53-62.
Abstract:The dextral compressive tectonic zones of N10°-30°W in Northeast Qinghai-Xizang Plateau is generally known as Hexi System. The system consists of three upwarped districts, four depressions and some fault zones located between the both of them. Its activity influences to the midlower crust, even to the bottom of lithosphere in eastern border. The Hexi System evidently control seismicity. Moderate earthquakes or greater ones mainly occurred in some parts where the edges of the first-class upwarped districts and the NWW fault intersect.
Zhao Zhijun , Wang Yuxia , Liu Xiujing
1989, 11(3):63-68.
Abstract:The Lingwu earthquake of Ms 5.5 on Aug. 10, 1987 is studied comprehensively. Before the seism, the direction of the principal compressional stress axis of the regional stress field is 268°. The strike of the structure where the earthquake occurred is 322°, it is 16km long. The seismic sequence belongs to the foreshock-mainshock-aftershock type. Foreshocks and aftershocks are distributed along two main active structure zones in Lingwu area. The mainshock is located at place where the two structures cross. The seismic gap appeared before the earthquake. The mechanical reason that a lot of seisms frequently took place in this region is due to the strong horizontal and vertical different motion.
1989, 11(3):69-77.
Abstract:Based on 3 natural events of late in the area of Longtan reservoir which is to await construction, this paper obtains the principal compression of mean N50°W in direction and the Q-values of about 23 and 360, respectively. It is proved that there is linear dependence of seismic moment M0 on magnitude ML, and linear independence of mean source dimension a or stress drop △σ on ML. It is estimated that after impounding, the reservoir is able to induce stronger earthquakes.
1989, 11(3):78-81.
Abstract:根据甘肃区域地震台网和全国地震台网测定,这次地震的基本参数是:
发震时刻:1988年11月22日01时46分1.7秒;
震中位置:北纬35°35',东经99°32',即肃南县城以南的祁连山中;
震源深度:20km;
震级:Ms=5.7。
1989, 11(3):82-88.
Abstract:工作中使用了三口水位观测井及五个水氡观测泉点的观测资料。三口观测井均位于南北地震带北段的六盘山地震带上,大地构造位置属于祁吕贺兰山字型构造体系的马蹄型盾地也(图1)。
Yan Zhide , Ren Tiesheng , Zhang Yaling
1989, 11(3):89-95.
Abstract:震级是描述一个地震的重要参数之一。目前在震级测定工作中还存在着一些问题,使得所测定的震级不统一而且不够精确,尤其是近震震级ML的测定更是这样。
1989, 11(3):96-98.
Abstract:四川省犍为县罗城地区(北纬29°17'-29°27',东经103°55'-104°10')位于威西盐矿厚度带上,历史上没有地震记载。四川省五通桥盐厂分别于1967年和1976年在罗城地区上了第一、二期基本建设工程,运用钻井注水采盐工艺对威西盐矿的岩盐进行开发利用。
1989, 11(3):99-100.
Abstract:
1989, 11(3):102-108.
Abstract:This paper describes the CSJP database comprehensively, which has been developed by the Information Research Office, the Earthquake Research Institute of Lanzhou. It is designed by VAX DATATRIEVE, VAX Common Data Dictionary softwares on VAX 11/750 minicomputer, so the CSJP database is an English documental database. It mainly collects journal papers about the earthquake prediction research from 50 Plus journalswhich are edited and issued in China. Among of them, 16 journals are edited and issued by seismological institutes or provincial seismological bureaus which belong to State Seismological Bureau. Referring the ISO and Chinese biliographical description rules, we design the format and data items [fields] of a documental record standard and in common use. The length of a record for a paper is fixed, 1898 bytes long, including abstract 1020 bytes. There are about 800 plus papers every year. Tapes or disks of the documental database can be exchanged or sold at home and abroad.
Sopyright:China Earthquake Engineering Journal