Yu Xuejun , Yao Lixun , Sheng Guoying , Hou Xiaoyu
1989, 11(1):1-10.
Abstract:In the preparing process the seismicity in preparing region is undergoing a quick increase process and a quiet process. Thus, the quasi-stable state process of seismisity in the area is upset in the preparing period. The spacial and temporal heterogeneity is clearly shown.
According to the view two indices that indicate the heterogeneity of seismic process in a area were defined: the heteropic degree of seismic frequency Fd and the heteropic degree of seismic energy Ed.
On the basis of expounded theory eight earthquakes (Ms=6) occurred in China have been examined, and the correlation between future earthquake magnitude and abnormal time of Fd and Ed was given. Applying the correlation formula to Diebu earthquake (Ms=5.9, on Jan.8,1987) in Gansu province we achieved good result. The two indices, Fd and Ed, have the meaning for the quantification of earthquake prediction method.
Zhang Cheng , Gao Shilei , Shao Shiqin
1989, 11(1):11-15.
Abstract:In 1985, we calculated the travel-time table of regional seismic waves by using a two-layer crustal model, H1=22.0km, Vp1=6.10km/—sec, Vs1=3.55km/sec; H2=29.5km, Vp2=6.47km/sec, Vs2=3.81km/sec; H=51.5km, Vpn= 8.17km/sec, Vsn=4.62km/sec. Besides giving the travel times ofp,s, P2, S2, Pn, Sn waves with the general travel-time table, it also gave the travel times of P1, S1 reflection waves at the surface of the middel layer and of Pm, Sm reflection waves at the Moho surface. This table is more practical than that calculated by a one-layer model of Gansu and its adjacent areas, and more accurate than that calculated by a four-layer location model of Gansu area. It is used conveniently.
He Genqiao , Zhang Bi'ao , Liao Yuanmo , Chang Qiujun , Wan Fuling , Guo Yuying
1989, 11(1):16-20.
Abstract:This paper deals with the features of concentration variation of the microgases (Rn, H2, CO2, Hg)along the northeastern segment of Aerjin fault, on which we do 10 plus profiles from Annanba to Kuan-tanshan about 400 plus km. The fault is segmented according to the concentration variation of microgas and the recent fault activity is also discussed. It is suggested that it is a obvious segment of the re-cent activity from Annanba to Sangequan; it is general from Sangequan to Chelukou of Changma; it is relatively stable from Chelukou of Changma to Kuantanshan. Finally, the preliminary strong earthquake forecast on the northeastern segment of Aerjin fault is made.
1989, 11(1):21-27.
Abstract:Discusses "Mogi Period" according to uniform earthquake catalogue revised by Abe Katuyuki. Considers that "Mogi Period" really conforms to actual seismic activity. Not only dispels the contradition that existed in the beginning of this century, but the "Mogi Period" can date back to 19th century. Strong earthquake activities of some regions in inland of China is good interrelation with the "Mogi Period", and estimates the trend of future seismic activities in the coming 20 years.
Zhang Deqi , Wang Shengfei , Zhang Nianxiao
1989, 11(1):28-32.
Abstract:Employing P.R. Banister’s engineering expression for horizontal electric dipole quasi-static electromagnetic field, makes an estimation hereof the peak current moment IL on the basis of the ultra-low frequency observasions for the electromagnetic waves before two esrthquakes: Liyang Ms=6.0 on July 9, 1979 and South Yellow Sea Ms=6.2 on May 21, 1984. The result is: the magnitude of IL=107-108 A.M for Liyang earthquake and the magnitude of IL=10Ω A.M for South Yellow Sea earth-squake. This is just the same as what we estimated on the principle of crust wavequide.
1989, 11(1):33-40.
Abstract:This paper presents the basic parameters and moderate term pre-diction of the Sheyang earthquake (M=5.1)on Feb.17,1987. Based on the urgent and short anomalies before the earthquake, the author finds that these anomalies have periodicity, synchronism and relativity in temporal distribution and the space distribution appears character of "multi—source" precursory field. In view of the above, also discusses the possibility of predicting moderate and strong earthquakes in Jiangsu Province and South Yellow Sea areas.
1989, 11(1):41-47.
Abstract:In this paper, the synchronous activity natures and the tectonic charac-teristics of the deep focus and shallow focus earthquakes in the continent of northeast China have been studied. It is considered that the action of the Northwest Pacific Plate is the dynamics of synch-ronous activity of deep focus and shallow focus earthquakes. The Northwest Pacific Lithosphere Plate underthrusts in the upper mantle of Huichun area with the depth of 590km. It results in the activities of deep earthquakes. Meanwhile, it affects the shallow earthquake activities in Tanlu Rift Zone and the fault zone in the margin of Songliao Basin and its adjacent area directly.
Zhou Hainan , Feng Rui , Zhang Boming
1989, 11(1):48-52.
Abstract:The crustal and upper mantle structure of Kunlun-Chaidamu-Qinling-Dabie tectonic zone is studied by using the data available from Chinese Digital Seismographic Network. The average thickness of sedimentary layer is about 8km with a shear wave velocity of 2.62km/s. It is noted that average velocity of 3.50km/s in the crust is relatively low, and there exists a low velocity layer in the lower crust. The undulation of the crustal thickness from East to West China is not great, being about 48km thick on average. The low velocity layer in the upper mantle appears at the depths of 70 to 90km. Such tectonic feature is different from both platform and the Tibetan plateau. Being a transition tectonic zone among geological blocks, it is indeed an independent tectonic unit of the crust in China.
1989, 11(1):53-58.
Abstract:In this paper, formulae of calculating best operating position of horizontal pendulum tiltmeter are derived, choice of precision and para-meter are discussed. After horizontal pendulum tiltmeter is fast and precisely adjusted by using this method given in this paper, tiltmeter operates in best position. Deflection angles of true operating position of instruments from their best positions, which were installed at more than 50 stations in China, were determined by using this method, and these instruments were readjusted, better effect was taken.
Wu Jingnong , Gong Gangyan , Yan Yuding , Xie Yuanding
1989, 11(1):59-67.
Abstract:This paper deals with laboratory investigation into Permeability of intact rock, natural facture rock under lower pressure (maximum test pressure is 20MPa). Four materials (granite, metamorphic rock, marble and cement block) have been tested in experiment by using six kinds of ways. Tile results show that permeability of intact rock under lower pressure is of 0.001 md magnitude and fractural rock is of 1 md magnitude, and rock permeability is clearly related to stress state and loading way.
1989, 11(1):68-69.
Abstract:1986年我们建议把统计物理学中相态突变前刻发生的现象(即临界现象)用于地震预报(国际地震动态,1986年8期)。该文讨论了涨落加剧和长程关联在地震顶报中的应用。
1989, 11(1):70-72.
Abstract:众所周知,蕴震系统是一个复杂的非线性的耗散大系统,也就是说它里面一定存在着正反馈和负反馈的共同作用,单纯的正反馈或负反馈机制很难反映它们的变化。对于地震来说,如果有利于地震的因素占据了主导地位,地震将发生,如果抑制地震的因素上升到主导地位,蕴震系统将解体。
1989, 11(1):73-78.
Abstract:对于L1、Lg1和Lg2波,有人认为是短周期面波,也有人认为是导波或是多次反射波,对此已有较为详细的研究结果,但对纵波性质的同类型波却研究甚少。
Liu Yaowei , Yan Xianchen , Zhang Zeng , Wang Changling , Jiang Dayong , Shen Kejin
1989, 11(1):79-81.
Abstract:一般认为原生汞直接来原于地幔,在地幔物质的长期分异过程中,由于汞具有较高的挥发性,汞蒸气沿深部断裂活动和运移,并在深大断裂上部附近富集。在低温热液型岩浆的分异过程中,岩浆残余液中的汞也会沿次级深大断裂运移或活动,并在断裂上部富集,有时形成含汞的矿体。
1989, 11(1):82-82,86.
Abstract:山丹红寺湖泉点位于龙首山北麓的红寺湖附近,在构造上处于龙首山北西西向断裂与北北东向断裂的交汇部位,系断裂上升泉。降雨和浅层地下水对该泉影响甚微,外界干扰较少。
1989, 11(1):83-83.
Abstract:在1981年7月12日和13日,川西地区普降暴雨,井研县天云公社附近从7月12日夜间0时至7月13日午后6时,降雨量达到135毫米,可称为大暴雨。
1989, 11(1):84-84.
Abstract:1979年以来,笔者就开始了本课题的研究工作。经过统计,发现我国大陆地区大震的发生基本上与台湾至广东东沙群岛地区的大震有一定呼应关系。
1989, 11(1):85-86.
Abstract:近年来国际上常使用体波震级mb,由于其具有一定的物理意义,各种地震报告中一般都有mb值。
1989, 11(1):87-92,72.
Abstract:对地震事件的统计预报是地震危险性分析中的一项基本工作。因此,近十几年来,地震学和工程地震学方面的研究者们发展了多种预报地震的概率模型。但由于在这些模型中需要较多的参数,因而大大限制了这些模型的应用。本文在前人工作的基拙土,提出了一种新的双态泊桑模型。本文提出的模型较目前人们所常用的平稳泊桑模型有所改进,且方便、实用,在一定条件下可转化为平稳泊桑模型。双态泊桑模型能较好地反映出地震活动的高潮期和低潮期,因此,在预测地震危险性时效果较好。本文还以海原断层为例,用双态泊桑模型计算了未来50年内该断层对兰州市的影响,並将所得结果与用平稳泊桑模型计算的结果进行了比较。
Sopyright:China Earthquake Engineering Journal