云南地区GNSS连续观测短临异常指标提取及效能评价

通过对云南地区43个GNSS连续站2011-01~2018-12站点位移时间序列原始数据进行深加工处理，在计算应变参数格网时间序列的基础上，分别提取适合云南地区M≥5.0地震短临预测的面应变及最大剪应变短临异常指标；并基于其间发生的27个M≥5.0地震，采用R值评分法对异常指标进行预测效能评价。结果表明：1）两种异常指标对云南地区M≥5.0地震的发震时间具有较好的指示意义；2）当预测窗长设置为30 d或60 d时，在相同预测窗长下，最大剪应变短临异常指标的预测准确率高于面应变短临异常指标；3）通过对同一异常指标进行不同预测窗长的对比发现，面应变短临异常指标的最佳预测窗长为90 d、最大剪应变短临异常指标的最佳预测窗长为60 d（对于27个地震，二者预测结果均为：报对23个，漏报4个，预测准确率为85.19%）。

GNSS Continuous Observation Short-Term Anomaly Index Extraction and Effectiveness Evaluation in Yunnan Area

Through the deep processing of the original station displacement time series data of 43 GNSS continuous stations in Yunnan from January 2011 to December 2018, based on the calculation of the strain parameter grid time series, the surface strain/maximum shear strain short-term anomaly indicators suitable for the short-term and imminent prediction of M≥5.0 earthquakes in Yunnan area are extracted respectively. Based on 27 earthquakes with M≥5.0 that occurred during the period, we use the R value scoring method to evaluate the predictive efficiency of the anomaly indicators. The results show that: 1) Two anomaly indicators have a good indication of the occurrence time of M≥5.0 earthquakes in Yunnan area. 2) When the forecast window length is set to 30 or 60 days, the prediction accuracy of the short-term and impending anomaly index of the maximum shear strain is higher than that of the surface strain under the same prediction window length. 3) Through the comparison of different prediction window lengths on the same anomaly index, we find that the best prediction window length of the surface strain short-term and imminent anomaly index is 90 days (for 27 earthquakes, 23 were reported correctly and 4 were missed. The predictive accuracy rate is 85.19%), and the best prediction window length of the short-term impending abnormality index of the maximum shear strain is 60 days (23 correct reports, 4 missing reports, and the predictive accuracy rate is 85.19%).