earthquakesn.地震名词earthquake的复数形式.earthquaken.地震earthquake statistics地震统计(学)earthquake activities地震活动性earthquake perdiction地震预报Earthquake clustering地震丛集Earthquake precurso r地震前兆earthquake exploration地震勘探earthquake preparation强震孕育earthquake premonition地震前兆earthquake periodicity地震周期性earthquake forecasting地震预报