The Primary Study On The Strong Earthquake Increase (Decrease) Earthquake Model Based On Stress Release

Based on the Stress Release Model, this article has improved the model in order to study the strong earthquake increase (decrease) earthquake problem. The stress function of stress and strain field theory around a crack in Rapture Mechanics has been introduced. From the angle of mechanics, the stress change features of an epicentre and in any point in space have been studied. The existent relations between the stress change rule and the strong earthquake increase (decrease) earthquake function of the other sections on a fault zone and among parallel faults. The strong earthquake increase (decrease) earthquake model has been built and called the Increase (Decrease) Earthquake Model Based On Stress Release. The model can estimate the earthquake risk after a strong earthquake occur in an structure area and the study results have relatively important significance for earthquake prediction and the earthquake risk estimate.In this article, the idiographic study about Ms≥5 moderately-strong earthquakes recorded since there had the historical records in Ningxia area has been done by using the stress function and the Increase (Decrease) Earthquake Model Based on Stress Release. The results have showed that: That the East Side Helanshan Fault in north Ningxia occurred a 8.0 magnitude earthquake in 1739 has played the obvious decrease earthquake function on the Luhuatai Fault, the Yinchuan-Pingluo Fault and the Yellow River Fault which approximately parallel to the East Side Helanshan Fault. And that the Haiyuan Fault in south Ningxia occurred a 81/2 magnitude earthquake in 1920 has also played the obvious decrease earthquake function on the Xiangshan-Tianjingshan Fault, the Yancongshan Fault and the Niushoushan-Luoshan Fault which approximately parallel to the Haiyuan Fault and at the same time, the increases earthquake function on the Middle East Section of the Qilianshan Fault Zone.At last, this article has studied exploringly the influence of Indonesia 8.7 strong earthquake occurred in 2004 by using the stress function and the Increase (Decrease) Earthquake Model Based on Stress Release. The results have showed that this strong earthquake has played the increase earthquake function on the other sections of the Sumatra...