摘要
通过对测震学各单项指标的预测效能调研 ,为进一步提取前兆信息 ,选择了 7项测震学指标 :频次、地震蠕变、 b值、缺震、η值、GL值和调制比 ,进行综合概率分析。7项指标对关注地区的全时空扫描并考虑了空间单元异常与中强震地点对应的模糊关系 ,得到指标在各空间单元异常后发生中强震的条件概率。根据历史上每个单项指标的预报效能求计算综合概率时的指标权重 ,按贝叶斯定律得到相应不同指标在不同时间窗和不同空间单元时中强震发生的加权综合概率。计算结果 (1 970年以来 )表明 ,对华北地区和川滇地区这一综合概率方法预测效能的 R值评估超过 0 .
By means of single item index, 7 seismological indices, including frequency, earthquake creeps, b value, average magnitude, η value, GL value and modulation ratio, are selected for synthetical analysis in order to extract the further precursory information. The time space scanning is made for all seismological indices. Considering the fuzzy relation between space unit anomaly and the location of moderate strong earthquakes, the condition probability for occurrence of moderately strong earthquakes after the anomaly appearance in each unit has been obtained. Then the index weighting of the synthetical probability is inferred based on the prediction efficiency of each single index in the history, from which the weighted synthetical probability for occurrence of moderately strong earthquakes is obtained by using the different space units and different time window according to Bayes rule. The results (since 1970) indicate that R value of prediction efficiency of synthetical probability method is greater than 0.5.
出处
《地震》
CSCD
北大核心
2001年第2期46-52,共7页
Earthquake
基金
地震科学联合基金会重点资助项目!( 95-0 7-4 31 )
