Earthquake prediction for Palau Islands
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摘要: 在地震孕育过程中，由于构造应力的作用，使震源系统的应力逐渐增强。当应力增强到一定程度时，震源系统将会变得极不稳定，地震孕育进入中短期阶段。基于这个认识，本文利用视应力研究了帛琉群岛地区地壳构造应力的变化，同时还分析了地震活动的地球自转相关性。得到的结果表明在未来2—3年内，这个地区具有发生MS≥8.0地震的危险性。Abstract: In the process of earthquake preparation, stress in the focal area could increase with tectonic stress. When the stress increases to a certain level, the focal area will become unstable. On the basis of this view point, the variations of crustal tectonic stress in Palau Islands area were investigated by using apparent stress in this paper. Meanwhile, the correlation of seismic activity with earth’s rotation was examined. The results indicate that there could be a risk of MS8.0 occurring in this area in the next two to three years.
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Key words:
- Palau Islands /
- apparent stress /
- Earth’s rotation /
- correlation /
- earthquake risk prediction
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图 2 视应力异常区 （图中红色实线所围成的区域）
Figure 2. Apparent stress anomaly area （solid red rectangle）
图 3 视应力时间变化曲线 （图2中红色实线所围成的区域）
Figure 3. Apparent stress as a function of time (the solid red rectangular area in Figure 2)
图 4 （a） 2018年发生在地球自转加速或减速期间的M≥5.0地震震中分布。加速期间地震集中发生在蓝色实线围成的区域内。（b） P值随时间的变化 （红色区域表示95%置信区间）
Figure 4. (a) Spatial distribution of event count for earthquakes (M≥5.0), and earthquakes that occurred during the earth’s rotation are concentrated in the blue rectangle. (b) P-value as a function of time for earthquakes (M≥5.2) that occurred in the blue rectangle (the red area indicates the 95% confidence range)
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