直接多点测位法与华北地震

本文根据大华北地区地震分布的空间特征,提出“直接多点测位法”,旨在用来预测该区域内未来可能发生强震的地区。该方法的具体步骤是,在任一地震区外选取4个参考点,将该区内发生的各次地震震中相对参考点的地心夹角表示在坐标平面上,使可从中找出震中空间运动规律。震中的迁移符合马尔科夫过程。由此,可预测该区域未来发震的概率。经预测检验,该方法是可行的。本文还利用该方法对华北地震区未来地震趋势作了预测。

Safe mining technology of undersea metal mine

Xinli district of Sanshandao Gold Mine is the first subsea metal mine in China.To achieve 6 kt/d production capacity under the premise of safe mining,high-intensity mining might destroy the in-situ stress filed and the stability of rockmass.According to sampling and testing of ore-rock and backfill and in-situ stress field measurement,safety factor method calculation model based on stress-strain strength reduction at arbitrary points and Mohr-Coulomb yield criterion was established and limit displacement subsidence values under the safety factor of different limit stoping steps were calculated.The results from three years in-situ mining and strata movement monitoring using multi-point displacements meter showed that the lower settlement frame stope hierarchical level filling mining method,mining sequence are reasonable and rockmass stability evaluation using safety factor method,in-situ real-time monitoring can provide the technical foundation for the safety of seabed mining.

大同地震后华北地震形势

采用几种方法分析了大同地震后华北地区的地震形势。根据地震活动和构造特征划分了研究区域，用作者提出的灰色线性预测模型及可公度性预测了发震时间，用作者提出的多点测位法预测了地震危险区并用近百年大陆地震活动特征估计了震级。综合分析结果认为，１９９５～１９９６年华北发生ＭＳ≥５．５地震的概率为Ｐｔ｛１９９５～１９６６｝＝７／１１～８／１１，地震危险区位于晋东南的概率为ＰＳ＝７／８～１。