中国钻孔应变观测能力及在地震预报中的应用

摘要

对钻孔应变观测在地震预报中的应用情况的分析结果表明,钻孔应变震前异常多数情况下分布在远离震源的区域上,而近震源区域却较少观测到显著的前兆.这种观测事实一方面可能反映了钻孔应变观测仪器数量有限和钻孔应变观测场地分布不均匀对分析结果的影响;另一方面也可能反映了震源区的力学性质,即震前震源区呈现应变高积累、小变形的特征.%The main states of borehole strain measurement, a variety of earthquake cases were analyzed. The results show that the borehole strain anomalies before earthquakes in most cases were located in the region far from the source, while near the source region significant precursor were rarely observed. This fact, on the one hand, may reflect the lack of the borehole strain sites and uneven distribution of them; the other hand, may reflect the mechanical properties of the focal region, that in a focal region before the rupture there are high strain accumulation and small deformation.