内蒙古乌拉特后旗—临河地区地震活动的预测效能评估

The Prediction Efficiency Evaluation of Seismicity in Wulatehouqi-Linhe Area

基于中国地震台网地震目录,在对目录的完整性评估并确定起算震级基础上,统计内蒙古乌拉特后旗—临河地区地震活动的起伏特征,以及小震活动和鄂尔多斯块体西北缘中强以上地震的对应关系。分析表明,乌拉特后旗—临河地区地震频度的升高与鄂尔多斯块体西北缘中强以上地震有较好的对应关系;ML≥2.2地震的半年频次N≥10可以作为中强以上地震的预测指标,预测时间为异常出现后1a内,R值评分和molchan图表法检验均显示地震频次的预测效能是显著的。

Based on China seismic network catalog,after the integrity assessment of the catalog and to determine the threshold magnitude,the fluctuation characteristics of seismic activity in Inner Mongolia Wulatehouqi-Linhe area and the relation between seismicity and strong earthquakes in the northwestern margin of Ordos block were analyzed.The analysis shows that there is a good correspondence between the increase of earthquake frequency and the moderate strong earthquakes in the northwestern margin of Ordos block.The half year frequency of ML≥2.0 earthquakes greater than or equal to 13 can be used as a predictive index of MS≥5.0 earthquakes.The prediction time is one year after the appearance of the anomaly.The R value score test and Molchan chart test showed that the forecast performance of earthquake frequency is significant.