Dynamic Determination Of Earthquake Influence Field Based On Multi-source Information In Different Periods

China is one of the countries with the most frequent earthquake disasters and the most serious threat of earthquake disasters in the world.In terms of global geographical distribution,China is located in the southeast of Eurasian plate.Due to the geographical location and plate movement,the Pacific plate and Indian Ocean plate squeeze China at the same time.Therefore,it becomes a zone with frequent earthquake activities at the junction of plate movement,That is,several major earthquake zones in China.Destructive earthquakes often occur in these areas,and at the same time they cause extremely serious losses.According to the statistics of relevant departments in China,earthquake disasters cause the most deaths,far more than other types of natural disasters.After the earthquake,it will bring great damage to the disaster area.For the people in the disaster area,their life and property security are facing a great threat.In order to minimize the damage and loss caused by the earthquake,the earthquake emergency rescue department will carry out the corresponding work in the first time after the earthquake.But because the scope of earthquake and the degree of damage are far beyond imagination,the earthquake emergency rescue work is also facing great challenges.For the earthquake emergency rescue work,the biggest difficulty is not clear about the damage situation and the degree of damage in the earthquake area.In this case,when the work is carried out,no targeted work deployment can be made.If the distribution of the earthquake impact field can be obtained quickly after the earthquake,it will bring us great guidance for the earthquake emergency rescue work,It can also provide the reference for the command department to make decisions.The earthquake intensity influence field refers to the influence caused by earthquake.Generally,it is expressed by the seismic intensity isoseism line,which is distributed in ellipse,and the intensity level from inside to outside is gradually reduced,and the center is the extreme earthquake area.This study aims to collect seismic data at different stages after earthquake and calculate the data,and quickly get the distribution of earthquake intensity influence field after the earthquake,which can provide reference for the earthquake emergency rescue.Among them,for the phased seismic data,this paper defines three stages.The first stage is defined as the basic data of the earthquake within 10-15 minutes after the earthquake occurs.The seismic data collected in this stage are the basic data of the earthquake,including magnitude,epicenter position coordinate,depth data of the source,etc,In this stage,the distribution of seismic intensity in the first stage can be obtained by selecting the appropriate attenuation relationship of seismic intensity to calculate the basic seismic data;The second stage is defined as two hours after the earthquake.Within two hours after the earthquake,the aftershock information of this stage is collected.Through the method of linear regression,the data of aftershocks are regression analyzed,and the long axis direction of the seismic intensity influence field is obtained,and the seismic influence field generated by the first stage is modified;The third stage is defined as within 12 hours after the earthquake.During this stage,the seismic data collected include seismic instrument intensity data,investigation intensity data and aftershock data within 12 hours.In this stage,the collected intensity data are calculated,and the long axis direction of the earthquake impact field is determined by using the aftershock data within 12 hours,Then,the results of the second stage are revised comprehensively by using the calculated results,and the results of the seismic intensity distribution in the third stage are obtained.In this study,first of all,through a large number of relevant literature,the establishment,development and applicability of the seismic intensity attenuation relationship have a certain understanding;Secondly,the method of intensity correction is studied,that is,how to modify the influence field of seismic intensity by intensity data.Finally,the influence of aftershock distribution on the distribution of seismic intensity is studied.The relationship between them is explained,and the method of using aftershock data to modify the distribution of seismic intensity is given.Taking Lushan earthquake and Changning earthquake as experimental examples,the experiment based on the research ideas is carried out.The results of the distribution of seismic intensity of Lushan earthquake at different stages are calculated.The results are compared with the results of the final Lushan earthquake intensity map issued by the China Seismological Bureau.The results show that the results of this study are consistent with the actual results in high intensity areas,It is believed that it can provide some reference for earthquake emergency rescue work after the earthquake.