Abstract: By use of mean focal mechanisn solutions from 12 stations and reliable those forsmall and moderate earthquakes,this paper is to discuss characterstic distributions of regional stress fields in the study area.The results indicate that the distribution of the stress field north of 32癗 in thisarea is characteristic of the North China block;south of 32癗,it is characteristic of atransition of the North China block to the South China one;souther Anhui is characterises of South China.These characteristics serve to define the southern boundary of the North China block.

摘要： 本文以安徽省境内的12个地震台的平均机制解以及较为可靠的中小地震机制解结果出发,讨论了安徽境内区域地震的应力场分布特点。在与华北地区的应力场方向检验结果的基础上,认为:本省北纬32。以北地区的应力场分布具有华北块体的特点;而北纬32°以南的中南部地区已具有华北块体向华南块体过渡地区的应力场分布特点,而皖南地区已属于华南应力场的范畴。上述分布特点为划定华北块体的南边界提供了应力场方面的依据。