Space-time Symmetry Study Of Earthquake Disasters In Japan

Japan is located in the circum Pacific seismic belt,geological activity,frequent earthquake disasters,resulting in economic losses and casualties immeasurable.Therefore,It is of great theoretical and practical significance to study the history of strong earthquakes in Japan,to judge the trend of time and space disasters and to explore the related factors of strong earthquakes.The paper collects and analyzes the data of historical earthquake disaster in 1900-2016.According to the geological structure of Japan,Japan is divided into the Northeast seismic region,the central seismic region,the southeast seismic region and the southwest seismic region.Based on the symmetry,this paper analyzes the history and space-time symmetry of the strong earthquake disaster by using the methods such as the degree of publicity,the butterfly structure,the structural system,the spatial symmetry and the epicenter migration,and determine its future development trend.Finally,the factors affecting the earthquake disaster in Japan are analyzed.The main conclusions:(1)Found in the analysis of historical earthquakes in Japan earthquakes with frequent bursts,and seasonal characteristics in time;showing the west east many obvious characteristics in space,and Ms>7.9 earthquake occurred in the eastern region of Japan,Ms>7.3 strong earthquakes occurred in the volcano belt.(2)Japan,the Northeast seismic region,seismic region,central region and the southwest of different earthquake magnitude earthquake zone showed good time symmetry in 1900-2016.Beautiful butterfly structure,commensurability structure clear.The signal of Japan Ms?7.5 earthquake is strong in 2019;the Northeast seismic zone is Ms?6.7 earthquake in 2020;the central area and the southeast seismic signal of strong earthquake is relatively strong,which may occur Ms>7.2 and Ms>6.9 earthquake in 2018;Ms?6.8 earthquake signal in Southwest China in 2017.(3)Shows that in Japan and the earthquake area 1900-2016 different magnitude earthquake symmetry in space research,Japan next Ms>7.5 earthquake epicenter will be moving to the northeast direction,namely east of 141 °E,in the vicinity of 39.2 °N;Northeast seismic region next occurrence of Ms>6.7 earthquake epicenter migration to the northeast,that is 144.5 degrees,42.8 degrees east of E N in the area near the north;Ms?7.2 earthquake in central earthquake zone occurred in 142 degrees,39.2 degrees east of E N to the north near the southeast area;earthquake zone next Ms more than 6.9 strong earthquakes may occur in east of 140.2°E.In the vicinity of 32.9°N;the southwest earthquake zone next time Ms>6.8 earthquake will occur at the area of east of 133.2°E,north of 33.6°N.(4)Effect of 1900-2016 years of strong earthquakes and sunspots,lunar and earth rotation and El-nino events and other related factors through the analysis,draw the following conclusions:? The Japanese and the different earthquake magnitude earthquake disaster occurred mostly in sunspot activity decline,year ratio as high as 79.2%,75%,71.4%,70.9%and 78.3%,the regional earthquake year and the sunspot cycle corresponding relationship is different.?The Japan Ms?7.5 strong earthquakes occurred in the high probability of bottom chord,the Northeast seismic region and southwest China earthquake zone is larger in the probability of earthquake shuori,central earthquake zone Ms?7.2 earthquake occurred in the first quarter and third quarter with equal probability,each accounted for 35%of the proportion of the total area,Southeast of Ms>6.9 earthquake the maximum probability of strong earthquakes occurred in the future.?During the period of 1900-2016,the magnitude of earthquake is more inclined to occur in the deceleration period of the earth rotation.The proportion of the year reached 58.33%,54.1%,80.95%,50%and 52.2%,respectively,in which the central seismic region is most sensitive to the deceleration of the earth's rotation.?During the period of 1900-2016,there is a certain correlation between the earthquakes and El Nino events in Japan and the earthquake zones.It is found that El Nino events are more strongly correlated with stronger earthquakes.There is a close relationship between Japan Ms?7.5 earthquake and the El Nino event,88%of Japan's Ms more than 7.5 years after the earthquake occurred or occurring in one to two years of El nino.?The period of 1900-2016,has a good relationship with Japan and the earthquake in Northeast China and North China earthquake,especially in the northeast.Japan Ms>7.5 earthquake in the 2 years after the earthquake,Ms?5.5 the Northeast verification rate reached 77.76%,North China Seismic verification rate of 27.78%.North China verification Ms?5.5 earthquake and earthquake area southeast of the highest rate is 61.11%,Ms?5.5 earthquake in Northeast China;in addition to verification and the Northeast seismic region was 55.56%,and the other three earthquake area verification rate was 66.67%.In this study,the time and space of the strong earthquake in Japan in the next few years are determined,and the case of strong earthquake is added.