泉州市中心城区区域地壳稳定性分析

在前人工作成果的基础上,对泉州市中心城区的区域地壳结构、区域地质构造、新构造运动、区域构造应力场和区域地震活动性进行综合分析.分析结果表明,泉州市中心城区在第四纪中更新世之前位于环太平洋中、新生代构造一岩浆活动带中,地壳运动频繁而又强烈,区域地质构造复杂;现代处于菲律宾海板块对欧亚板块挤压形成的"台湾动力触角"影响区,但区内的断裂不具全新世活动性,新构造运动不强烈,有史以来未见≥5.0级地震记载,属于地壳相对稳定区,未来遭遇6.0级地震的危险性不大,其地震破坏性影响主要来自周边孕震区,特别是东部海域,与"台湾动力触角"的作用和滨海断裂带的活动有关.

Stability Analysis of Regional Crust in Downtown of Quanzhou City

Based on the previous geological data, the authors made a comprehensive analysis of the regional crustal structures, regional tectonics, neotectonic movement, regional structure stress show City i field and regional seismicity in the downtown of Quanzhou City. The analytical results that before the middle Pleistocene epoch of Quaternary the downtown of Quanzhou s situated at the Mesozoic and Cenozoic tectonic-magmatic mobile belt in the circumpacific belt, the movement of earth crust is frequent and violent and the regional tectonics is tanglesome in the surveyed area. In modern times, it exists in the influence area of Taiwan dynamic tentacle formed by the extrusion pressing of the Philippines sea plate against the Eurasian plate. In the surveyed area the fractures is not active, the neotectonic movement is not violent and there are non-records of more than 5 magnitude of earthquake throughout history of Quanzhou City. Therefore, it belongs to a relative stabilization zone of the crust. In the future it is impossible to burst out more than, 6 magnitude of earthquakes and the influence of earthquake damage mainly comes from the seismogenic zone of its peripheral area, especially the eastern sea area. It is inferred that it has some relations with the effect of Taiwan dynamics tentacle and the movement of offshore fracture zones.