摘要
Starting with an analysis of the characteristics of the geophysical field, this paper puts forward the evidence for determining the NS-trending tectonic zone on the basis of the east and west differences of NS-striking gravity gradient zone and gravity-magnetic field characteristics, and investigated the regional and deep geological-structural background for the formation of NS-trending tectonic zone as well as the corresponding relationship of the zoned distributions of the earthquakes. The NS-trending tectonic zone reflected by the gravitational gradient zone has not only inheritance manifested by its consistency with the central axis structure but also newborn nature of westward expansion.