河套带、汾渭带中等地震活动平静对中强地震的指示意义

The Meaning of Moderate Seismic Activity Quiet to Strong Earthquakes in Hetao Belt and Fenwei Belt

摘要:

以相邻2次地震的时间间隔作为统计量,对河套带、汾渭带1976年以来的地震活动平静异常进行了统计检验。结果表明河套带、特别是汾渭带中强地震之前大范围内中等地震活动的异常平静现象是明显的,河套带、张渤带发生的5次6级以上强震有4次发生在平静异常结束或在平静过程中。目前该区域中等地震平静时间已远远超过历史统计的最长时间间隔,未来一段时间河套带、张渤带及邻区存在发生强震的可能性。

Abstract:

The interval days between two earthquakes in the Hetao and Fenwei seismic belts are statistical analyzed. The result shows that there were obvious moderate seismic activity quiet phenomena before strong earthquakes in large range in two belts, especially in Fenwei belt. A- mong 5 Ms≥6.0 earthquakes since 1976, 4 events occurred at the end of the seismicity abnormal quiet period or in the quiet course. Now the moderate seismicity quiet time has surpassed the biggest time interval in history record, so there is possibility of strong earthquake in Hetao belt and Zhangbo belt in future.