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1.
为了在地震危险性分析方法中,较好地反映大陆内部地震活动的时空不均匀性,按照震级分档和空间概率分布函数的思路,本文选取并量化了多个地震、地质特征,以描述各震级档地震活动在时间上和空间上的性质.为避免同一因素的重复使用和主观作用的介入,文中引入了分量分析方法对特征进行正交变换.对变换得到的互不相关的新特征进行模糊综合评判,再结合七级以上强震发生后的减震作用,确定了各潜在震源区各震级档的地震年平均发生率作为例子,试算了京-津-唐-张地区的地震烈度区划图.该例子说明,本文的分析方法,不仅能反映华北地区地震活动的时空不均匀性,还避免了特征量的重复使用和专家判断的影响 相似文献
2.
Research on the principle and methodology of seismic zonation 总被引：1，自引：0，他引：1
Based on the cognizance of the temporal-spatial inhomogeneity of seismicity in North China, adopting the results of earthquake prediction in the past two decades and the currently used methods of seismic hazard analysis, and after some zonation trials in North China, some improvements on the zonation principle and methodology were made:
- Seismic zones were taken as statistic units where seismicity parameters were obtained. Tendency analysis was introduced. Earthquake annual average occurrence rates were estimated corresponding to the seismicity level in the future period;
- Average annual earthquake occurrence rates for a given magnitude interval of a specific seismic zone were assigned to potential sources considering the relative risk level among these sources. Thus, the risk of great earthquakes can be estimated.
- The probabilistic spatial distribution function under the condition of magnitude interval was suggested to reflect the temporal and spatial inhomogeneity of seismicity.
- An orientation function in the seismic hazard analysis model was adopted, which reflects the real condition of earthquake foci in China.
3.
本文基于对我国华北地区地震活动在时间和空间不均匀分布的认识,吸收了近20年来地震预测方面的科研成果,采用目前国际通用的地震危险性概率分析方法,通过对华北区划的试验,对地震区划的原则和方法提出了如下改进: 1.以地震带作为地震活动性参数的统计单元.引入地震活动趋势估计因素,评定表征地震活动水平的年平均发生率,以使区划结果同预测未来时间段地震活动水平相适应; 2.采用按震级挡次分配各潜在震源区的年平均发生率,可以合理地评估高震级地震的危险程度; 3.采用以震级挡次为条件概率的空间分布函数,刻画地震带内各潜在震源区之间发生相应震级挡次地震的相对危险程度,使区划结果更好地反映地震活动在时间和空间上不均匀性分布的特点; 4.在地震危险性分析计算中,引入了方向性函数项,使得分析模型更接近我国地震震源的实际情况. 相似文献
4.
The intterrelation among strong earthquakes and its application are emphatically studied in this paper. Taking North China
seismic region as study area, we have investigated how a great earthquake influence other strong earthqukaes in neighbouring
area? Does there exist earthqukae immunity phenomenon? If it exists, what distributional pattern did it has in space-time
domain? The results show that occurrence of earthquakes withM⩾7 has cetain immunity phenomenon to earthquakes withM⩾6 in North China. Among others, the immunity area of earthquakes withM=8 is much larger than that ofM=7. For earthquakes withM⩾8, the immunity area to the earthquakes ofM=7 is larger than toM=6.
Based on the above analysis, using some statistical methods, we gave the variational regularity of seismic immunity factor
with space and time, and explored its concrete application in seismic hazard analysis.
The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,15, 339–346, 1993. 相似文献
5.
In this paper, first discussing briefly the instantaneous spectrum theory. Then, the instantnaeous spectra and Fourier spectra
of three seismic sequences are calculated, and comparing them to explain the superior characteristics of instantaneous spectrum.
Finally, the earthquake tendency of North China is estimated by using the instantaneous spectrum theory. The results show
that not only the occurrence time of the coming large earthquake, but also its magnitude instantaneous can be estimated by
using instantaneous spectrum of the seismic sequence.
The Chinese version of this paper appeared in the Chinese edition ofActa seismologica Sinica,15, 68–75, 1993. 相似文献
6.
This paper has made a study of the relationship between the phases of seismic activities from 1966 to 1976 in the region of
the North China Block and the temporal and spatial evolution of temperature anomalies from February 1960 to January 1979 of
the greater North China. The main conclusions are: (1) The temperature variation from February 1960 (rise) to January 1977
(drop) and the temperature rises of September 1975 and February 1976 are connected with the beginning and conclusion of phases
of seismic activity. (2) The relation between the time-duration and the extent of temperature anomaly and that between these
two parameters and the energy released by an earthquake have high credibility. (3) If the time period of 16.5 years between
February 1960 and July 28, 1976, the occurrence time of the the great Tangshan earthquake, is divided into 18 time intervals
according to 0.618N, the earthquakes in this phase of seismic activity and temperature rises fall just into the same intervals.
The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,15, 76–82, 1993. 相似文献
7.
This paper has introduced the method of self-similarity analysis of time series into the analysis and study of earthquake
sequence, and then researched its application in earthquake prediction. As parameter of earthquake time series, we can take
the cumulated sum of the numbers of equivalent earthquakesQ=ΣN*, the numbers of equivalent earthquakeN*, maximum magnitudeM
max, average magnitudeQ=ΣN*, and the difference ΔN* between the numbersN* in two adjacent time intervals. The given method may be applied to analysis of long-period seismic sequences in different
regions as well as to anlysis of seismic sequence in the aftershock region of strong earthquake. For making quantitative analysis
the coefficient of self-similarity of earthquake sequence in order of timeμs was introduced. The results of self-similarity analysis were obtained for the earthquake sequences in North China, West South
China, the Capital region of China, and for the East Yamashi region of Japan. They show that in period or half year to several
years beforeM⩾7.0 andM⩾6.0 earthquakes occurred in these regions separately, the self-similarity coefficientμs calculated by using the above-mentioned parameters had remarkably anamalous decrease variations. The duration time ofμs anomaly depends on the earthquake magnitude and may be different from different regions. Therefore, the self-similarity coefficient
in order of timeμs can be considered as a long-medium term precursory index.
The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,15, 455–462, 1993. 相似文献
8.
This paper systematically summarized the relation of the abnormal change of He and H2 dissolved gasses in deep hot-water well at Beijing No. 2 Cotton Mill and their relation with seismicity of the region. An
empirical formula for the relation of the precursory anomaly of He and H2 gasses with the magnitude and occurrence time of earthquake has been derived. Two events of magnitude greater than 5 in North
China had been successfully predicted by using this formula.
The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,15, 490–497, 1993. 相似文献
9.
ＴｈｅｒｅｇｉｏｎａｌｃｈａｒａｃｔｅｒｉｓｔｉｃｓｏｆｓｅｉｓｍｉｃａｃｔｉｖｉｔｙｉｎＣｈｉｎａＺｈｅｎ－ＬｉａｎｇＳＨＩ，ＪｉａｎＷＡＮＧａｎｄＸｉａｏ－ＤｏｎｇＺＨＡＮＧ（时振梁，王健，张晓东）（ＩｎｓｔｉｔｕｔｅｏｆＧｅｏｐｈｙｓｉｃｓ，Ｓ... 相似文献
10.
In this paper, based on the previous study of practical use of seismic regime windows and seismic regime belts, the problem
of establishing a “seismic regime network” consisting of “windows” and “belts” is further posed and discussed according to
the observed fact that many “windows” and “belts” make responses to one earthquake. For the convenience of usage, the “seismic
regime network” is divided into two classes, the first class and the second one. The former can be used in tendency prediction
for long-term seismic activity in a large area, the latter used in short-term prediction in a small area. In this paper, after
briefly discussing the physical significance of “seismic regime network”, it is pointed out that this simple and easily used
method can be used to observe and extract seismic precursory information from a large area before a great earthquake, thus
it can provide a reliable basis for the analysis and judgement of seismic regime tendency in time and space. No doult, this
method is of certain practical significance.
The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,13, 161–169, 1991.
The English version of this paper is improved by Prof. Shaoxie Xu. 相似文献
11.
In this paper, the MYCIN inexact inference method in Expert System is applied to comprehensive earthquake prediction. And
it is proposed that the methods of determining various certainty factors, correcting correlation between anomalous evidences
and computing comprehensive certainty factor of occurrence of some moderate or strong earthquake. By use of these methods,
18 earthquake cases since 1966 in North China is tested with seismological anomalies in different seismogenic stage, and the
comprehensive certainty factors of occurrence of some moderate or strong earthquake are computed. At last some problems in
application are discussed.
The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,13, 328–337, 1991. 相似文献
12.
In this paper, by means of the statistical analysis method of stochastic spatial point process, statistical analysis of spatial
distribution of earthquakes in the large northern region of China is made. Emphasis is on the test and analysis of the complete
spatial randomness, correlation of earthquake distribution in the different magnitude interval and random labeling. It is
shown by the analysis that the spatial distribution of earthquakes in the large northern region is “clustered”, the distributions
of earthquakes in different magnitude interval are positively correlated and can be modeled by a two-dimensional process.
The results obtained in the paper can be used for the establishment of a reasonable spatial distribution model and have some
application in the reasonable estimation of seismic hazard.
The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,15, 129–135, 1993. 相似文献
13.
The theoretical acceleration spectrum of observation site has been obtained from source acceleration spectrum derived from
scaling law, using attenuation modelQ=Q
ν
f
η
. A comparison of a set of theoretical acceleration spectra with observation spectra has been made, and we have obtained the
attenuation model for observation site and seismic moment magnitude. We obtain thatQ
o=300,η=0.25 for Wuqia area, Xinjing Zizhizhou, and seismic moment magnitudes of 18 greater aftershocks of Wuqia earthquake occurred
in 1985. In order to obtain seismic moment magnitued conveniently, three functional tables of acceleration spectra at 1Hz
as the distances for variousQ value have been made. The seismic moment magnitude can be quickly measured from acceleration spectrum at 1Hz according to
these tables (epicenter has to be known).
The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,14, 435–445, 1992. 相似文献
14.
Based on Generalized Seismic Ray Theory (Helmberger, 1968), a new quickly linear inversion method from the data of seismic
waveform to seismic moment tensor and source mechanism for domestic earthquake is studied in this paper. Six moderately strong
earthquakes which occurred in Chinese mainland in the past few years are studied. The seismic source parameters of these earthquakes,
seismic moment tensors, scalar seismic moments, fault plane solutions and source time functionsetc, are obtained.
The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,15, 261–268, 1993. 相似文献
15.
发震构造特性是潜在震源区划分及其地震年发生率确定的重要依据。潜在震源区除了反映“未来具有发生破坏性地震的地区”的内涵外,还应反映高震级档地震具有相似复发特征的涵义。由于在地震活动性参数统计单元内,有一些具有不同本底地震的活动构造块体,为更好地反映地震活动的空间不均匀性,考虑潜在震源区的三级划分是有必要的。通过分析潜在震源区内高震级档地震的复发特征,计算预测时段内潜在震源区的高震级档地震的发震概率,采用预测时段内概率等效转换获得地震年平均发生率的方法,有助于在中国地震危险性分析框架内考虑潜在震源区的强震复发特性。另外,文中还对潜在震源区内特征地震次级震级档频度不足的特性和发震构造上强震非均匀性在地震危险性分析中的应用问题进行了探讨 相似文献
16.
IntroductionI.thasbeenpayingattentiontotheanomalousphenomenonbyseismologiststhattheearthquakeactivityoftenstrengthensinacertainspaceandduringacertaintimearoundthesourceareabeforeastrongearthquake.Mogi(1969)pointedoutthataringdistributiveareaofthestrengthenedearthquakeactivityoftenappearsaroundthesourcearea10to20yearsbeforegreatshock,whichcalledaringphenomenon(or"doughnut").Afterthat,otherscholarsreportedinsuccessionthatringdistributionofearthquakeactivityoccurredbeforeastrongertquakeorevenbefo… 相似文献
17.
According to geological tectonics and seismic activites this paper devided North China (30°–45°N, 105°–130°E) into four areas.
We analyzed the North China earthquake catalogue from 1970 to 1986 (from 1965 to 1986 for Huabei, the North China, plain region)
and identified forty-two bursts of aftershock. Seven of them occurred in aftershock regions of strong earthquakes and seventeen
of them in the seismic swarm regions. The relation between strong earthquakes with the remaining eighteen bursts of aftershocks
has been studied and tested statistically in this paper. The result of statistical testing show that the random probabilityp of coincidence of bursts of aftershock with subsequent strong earthquakes is less than six percent. By Xu’sR scoring method the efficacy of predicting strong earthquake from bursts of aftershock is estimated greater than 39 percent.
Following the method proposed in the paper we analyzed the earthquake catalogue of China from 1987 to June, 1988. The results
show that there was only one burst of aftershock occurred on Jan. 6, 1988 withM=3.6 in Xiuyan of Northeast China. It implicates that a potential earthquake withM
S⩽5 might occur in one year afterwards in the region of Northeast China. Actually on Feb. 25, 1988 an earthquake withM
S=5.3 occurred in Zhangwu of Northeast China. Another example is Datong-Yanggao shock on October 18, 1989 which is a burst
of aftershock. Three hours after an expected shock withM =6.1 took place in the same area. Two examples above have been tested in practical prediction and this shows that bursts
of aftershocks are significant in predicting strong earthquakes.
The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,13, 273–280, 1991.
Part of earthquake catalogue is from Jinbiao Chen, Peiyan Chen and Quanlin Li. 相似文献
18.
根据华北地区的地震目录,建立了4个空间光滑的地震活动性模型,并以这些模型为空间分布函数,将华北地震区每个地震带的地震年发生率分配到空间格点中,计算这一地区的地震危险性．结果表明,采用仪器记录地震计算得到的地震活动性模型和地震危险性结果能够反映华北地区现今的地震活动水平和地震危险性水平,符合人们对现今华北地区地震危险性的认识;采用历史破坏性地震（Mge;4.7）计算的地震活动性模型和地震危险性结果,较好地反映了华北地区中强地震活动区的地震危险性水平;以地震应变计算地震活动率,并根据点椭圆模型和线椭圆模型计算得到的地震活动性模型,能够较好地反映大地震的活动水平和空间构造特征．将根据4个模型计算得到的50年超越概率10%峰值加速度（PGA）分布加权平均,得到综合的华北地区PGA分布,并将该PGA分布与根据《中国地震动参数区划图》中综合潜源方案计算得到的50年超越概率10%的PGA分布做了比较,发现二者无本质差别,均能反映华北地震区的地震危险性水平．当然,二者也具有一定的差异:前者计算得到的符合PGAge;100 cm/s2条件的区域面积明显要比后者的大,而符合PGAge;250 cm/s2条件的区域面积则比后者的要小. 这主要是由于潜在震源区类型和空间分布函数不同造成的． 相似文献
19.
Meng-Tan Gao 《地震学报(英文版)》1993,6(3):713-719
The models currently used in the seismic evaluation of important projects, microzoning and seismic zonation are all for site.
Although seismic hazard analysis have been done for many sites in seismic zonation and microzoning, relationship among sites
is not considered in the final results. Studies show that it is impossible to get total hazard for specific area from the
results of the hazard analysis of sites. So, when we consider the total seismic hazard of a specific spatial distributed system,
methods for site are not enough. Author discussed the relation and the difference between system hazard and segments hazard
which form the system and proposed a seismic hazard analysis model taking spatial linear distributed series and parallel system
as an example. In aseismic design and earthquake disaster prevention decision, not only the seismic hazard of segments of
the system but also the total seismic hazard of the system should be considered.
The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,15, 347–352, 1993. 相似文献
20.
In this paper, the major idea is: when seismic stress accumulates to a certain extent, a stick slip earthquake will occur
on the fault plane. The seismic stress before and after the stick slip earthquake occurrence are both stochastic variables.
According to this idea, the model of double bounds of stochastic stress is proposed, and also it is used to analyse the seismic
risk of Xian Shui River Fault Zone in the coming 30 years, the result is similar to what the Seismological Bureau of Sichuan
Province has predicted.
The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,15, 477–483, 1993. 相似文献