甘东南地区中强地震多学科前兆协调性特征研究

THE HARMONIOUS CHARACTER OF MULTI-SUBJECT PRECURSORS BEFORE MODERATE STRONG ERATHQUAKE IN SOUTH-EAST OF GANSU PROVICE

通过对发生在甘东南地区三次中强地震前4个前兆学科以及测震学指标的研究,发现各学科前兆异常在时空上表现出很好的协调性特征.主要表现在:各学科异常持续时间均较短;各异常以中短期为主,有一定中期异常,临震异常不明显;从震前1年到短临阶段异常显示出向震中迁移的迹象;各异常点集中分布在低b值异常区.讨论了前兆协调性与地下流体和深部热物质的运移的关系.

Based on study of some precursors before 3 moderate strong earthquakes in southeast part of Gansu provice,it is found that all kinds of precursors show harmonious character in temporalspatial.The result shows that the anomalies last shorter time and mainly in middleshort term,but in impending term is not clear.From one year to shortimpending stage,the anomalies migrate to earthquake epicenter.The distribution of precursor anomalies and low b value are concentrated to same area.The relationship between the harmonious character of precursors and transportation of underground fluid and thermal material in deep crustal is discussed.