舟山群岛地区的地质构造背景

从大地构造、磁场和新构造分区特点等方面，对舟山群岛地区的地质构造背景作了较为详细的论述，指出该区处于基底构造交汇，新构造和地震活动强弱分区的过渡地带，新构造运动在中更新世之后趋于平稳；全新世为间歇性活动，强度较弱，基底由若干微块体组成，块体间为不稳定边界，舟山群岛及其海域深部以东西向、浅表部以北东和北东向构造为主，具有孕震和发震的地质构造背景。

ON GEOLOGIC TECTONIC BACKGROUND IN ZHOUSHAN ARCHIPELAGO AREA

We made detailed discuss on geologic tetonic background in Zhoushan Archipelago area,according to characteristics of geotetonics, magnetic field and neo-tectonic zoning. The study expressed that this area belonged to the transforming region of the junction of basement structure, neo-tectonic movement and seismic activity zoning; neotectonic movement changed as follows: from the intensity before Mosepleisocene to stable movement and then to intermittent motion in Holocene; basement consisted of micro-masses and the boundary was unstable; in Zhoushan archipelago and vicinity area, the main structure was in WE direction in deep layer and in NNE direction in shallow one; there existed the geologic tectonic background of seismogenic condition.