Li Haihua , Zhang Wenmian , Wu Dezhen , Yao Qinchun
1981, 3(4):1-8.
Abstract:In this paper, the data of the precursor of 65 intermediate magnitude earthquakes are analysed, which almost occurred at the northern portion of the North-South earthquake belt.
We have also analysed their characteristics and difficulties for the prediction. The countermeasure, method, procedure, and index of the synthetic prediction are preliminarily proposed. The practical and theoretical meaning are also described and discussed.
Chen Zhangli , Xue Feng , Lü Peiling , Zheng Sihua
1981, 3(4):9-16.
Abstract:In this paper, we have discussed the principal characteristics of the regional seismicity before the Tangshan earthquake(Ms=7.8) in particular during the mid-range of the development of the strong earthquake. After 1975 year, the anomalous variations undergo transition and recovery. These phenomena and low stress drop of main shock may show that during a period before the strong earthquake, the stress decreased with the further development of the strain.Analysising the anomalous increasing of ground-temperature near the seismic centre since 1975 year, it is suggested it is possible that as hot matter gush up from the deep of the earth,the strength of the medium decrease, so that the strong earthquake takes place.
Wei Siyü , Teng Jiwen , Yang Bingping , Hu Zhongyi
1981, 3(4):17-25.
Abstract:The Xizang Plateau is the most intense area for geothermal activities in our country the crustal structure is very complex and earthquake activities are extremely frequent.
Based on geothermal data and various features of geophysical fields in the region research and analyses has been made in this paper. A unified interpretion of the nature in the deep part of the crust is given. It indicates that the cause of geothermal distribution and its activity in Xizang Plateau is due to the high temperature in the crustal medium and the existence of melting or partial melting matter in the crust. The geothermal display is affected by the deep crustal structure and material migration and the geothermal energy is provided by the quantity of heat produced by the collision process of the Indian plate against the Eurasian plate and the magmatic intrusion.
1981, 3(4):26-31.
Abstract:In this paper, the authors have analysed the two kinds of different prediction methods, which are the induction-magnetic effect and the correlation between the seismology and geomagnetism, according to the basic concept of magnetism. The data of many years have been applied to examine the three concrete prediction methods statistically. It is thought that the combination of the amplitude-phase method and low point displacement plan is of a certain effects to predict the moderate-strong earthquakes, especially the seismic occurring time. Finally, the Leaping over prediction method linked to the earth-quake prediction of the various magnetic field has been discussed.
1981, 3(4):32-36.
Abstract:Some theories and measurement techniques of the electrochemical methods, ion selective electrode and Eh, are introduced simply in this paper.
On the basis of data obtained form the field of Lüjing earthquake (M=3.4) 1980, it is indicated that there are obvious precursory anomalies for the fluorine, nitrate and Eh before the earthquake. On the other hand, we accentuate that the electrochemical method have some excellent features, for example, less instruments required, simplicity of operation, convenient to observe at field, easily to make up measurment continually and automatically, etc. It is an effective and practicable method to set up comprehensively hydrochemical observation.
We are sure that these methods would play an important part in the research of prediction earthquake.
1981, 3(4):37-42.
Abstract:By analysing the data in the present articled about geological structures, landforms, crustal deformations, geophysical field, seismology and so on, we think that in Tianshui region there is an active South-North tectonic zone which has close relations with earthquakes.
1981, 3(4):43-48.
Abstract:The earthquake (M=6.0) of April 6, 1932 took place at the Huangtu gang, Macheng, Hubei province. The Yingshanjian-Sidaohe fault is a seismic breaked structure. Because of Yingshanjian-Sidaohe fault is a locked-up structure in the Huangtugang narrow block of upper well of Macheng-Tuanfeng abyssal fault, thereby, during the Macheng-Tuanfeng fault dislocated reverse-left-laterally, much of elastic strain energy was accumulated on the shear locked up structure and at last it was caused to be break spread, there occurred the earthquake of magnitude 6.This is a strong seismic pattern of rock breaked on secondary small fault which is control led by major fault.
1981, 3(4):49-55.
Abstract:Basing upon the date of seismological observations, this paper has discussed the stress field of seven zones of Ninxia region and has given the focal mechanism solutions of sixteen moderate earthquakes. According to the crustal deformation, the stress fields of the region are mainly subjected to a strong NE-NEE compressive stress. The stress field is controlled by the joint action of the Indian and Pacific plates, and the former plays the major function.
1981, 3(4):56-61.
Abstract:In the present paper, an analysis the data of the Ms=6.0 earthquake Haicheng, Liaoning Province on May 18,1978. has shown that the shock is a new fracture than stick-slip on the seismic Ms=7.3 fault surface.
On the basis of after-shocks data and some formulas of fracture mechanics, we estimated that the total energy of the earthquake is E=6.1×1021ergs; seismic moment magnitude is Mo=2.8×1025 dyne. cm and stress decreased to △o=113 bars. Besides, the occurence of the strong earthquake(Ms=7.3) has been conjectured in accordance with the aftershock division of earthguake (Ms=7.3) and the space variation of the level correlative variable caused by the quakes.
1981, 3(4):62-68.
Abstract:This Paper from the View point of science of medicine discussed some influences of events related earthquake on the organic functions of human body. The redistribution and the migration of crustal elements caused by earthquake may bring some harms to the organs of body; The coseismic geomagnetic variation and the magnetic storm which trigger earthquake may cause a series of physiological changes of healthy body, and lead to the aggravating an illness of patients and the predisposing to infection of organs; Infrasound generated due to earthquake may make potential injury in the internal organs of body and other organic effects. The radiations of earth light, the eruption of hot substance and the emission of various rays from underground may cauterize humans eyes, feet and skin. Abnormal behaviour of carriers of animals may bring. about sp reading of epidemic and infectious diseases. Because of above-mentioned cases,we proposed some vaccinating measures-and treating strategy against the diseases accompanied earthquake in order to eliminate and reduce dis aster.
1981, 3(4):69-72.
Abstract:1932年12月25日发生在我国祁连山区的昌马7.5级地震,对于人们研究大地震发生的地质构造条件方面,是一个值得很好总结的震例。1964年时振梁等对该地震的调查研究,提供了很宝贵的资料。1974年原兰州地震大队对这一地震继续开展工作时,笔者参加了半年实地考察。此次考察成果亦有所介绍。笔者至今以为,有关此次地震于地表出现的地震破裂带特征,特别在其空间展布、力学性质以及由此所反映的区域构造应力场特征等方面,尚有值得进一步研究之处。本文拟就一些问题作一探讨,并对前人研究中的某些问题进行商榷。
1981, 3(4):73-76.
Abstract:1971年3月23日、24日新疆乌什县东北约30公里处接连发生Ms=6.0、Ms=6.1级两个地震。震前,离震中90公里的阿克苏地电台根据自然电位异常对这次地震作了某种程度的预报。为了监视震情的发展,同年四月初我们在乌什县九眼泉台增设了自然电流观测。九眼泉台位于乌什城区西北燕子山北麓的九眼泉公园内。该台布设了东西、南北两个测道。南北道大致垂直泉眼走向,东西道大致平行泉眼走向。两道极距均为100米。
1981, 3(4):77-79.
Abstract:武都地电台自1974年12月以来,已观测到不少震前地电阻率突变的现象,特别是1976年8月16日四川松潘7.2级地震前后,以及距该台50公里范围内的很多小地震,都较好地显示了震前突然下降的特点。为了探讨震前地电阻率的突然下降现象与一定范围内的地震的发生是否有内在的联系,现将我台对应地震较好的一条测线(平行Ⅰ道,方向北西73°)观测到的部分短临异常资料提出来供大家讨论。
Liu Tinghui , Li Kelong , Wang Xianyao
1981, 3(4):80-82.
Abstract:1.概况柳湖泉位于平凉城北的公园内,属第四系全新统出露的冷水泉,主要是泾河水和降雨补给。泉点水温年平均为12℃。氡含量为15埃曼。使用的观测仪器是FD——125射气仪。2.水氡变化形态用五年水氡的月均值作为纵坐标,时间(月)作为横坐标作图。从图1中可以看出尽管每年的水氡值有差异,但变化趋势基本一致。即每年十二月到第二年一、二月份是氡值最低阶段,七、八月份是氡值最高阶段,整个变化图形呈正弦形曲线。
1981, 3(4):83-85.
Abstract:1.地裂缝的基本特征1977年8月-9月西安辛家庙铁炉庙一带相继发现地裂缝。铁炉庙地裂缝位于市东南郊渭河三级阶地内黄土塬前缘洼地的北侧,东起铁炉庙,经后村、小寨、西到吉样村,断续延伸约6.5公里,尤以铁炉庙地段最为发育。其总体走向为北70°东,倾角70-90°(一般为76°)。由数十条地裂缝组成裂缝带,宽度为8-20米,一般在10米左右。地裂所经之处,建筑物多被裂开。
1981, 3(4):86-87.
Abstract:西影深井处在西安凹陷东南坡大雁塔热异常带上,位于西安电影制片厂后院。井深2000.41米。给水层有两层,分别是:1520-1527米和1560-1617米。1417米以上的环形空间用水泥封死,因之工农业取水层和地表水与该井给水层无水力学联系。从水位观测资料分析中发现,水位的升降变化与气压的升降变化同步性很强,反映了气压是水位变化的主要因素之一。
Sopyright:China Earthquake Engineering Journal