中国东部新生代火山的迁移与大陆裂谷的扩张和大陆漂移

THE SHIFT OF CENOZOIC VOLCANOES AND THE SPREADING AND DRIFTING OF CONTINENTAL RIFTS IN THE EASTERN CHINA

邓晋福 赵海玲 叶德隆 路风香 莫宣学

Deng Jinfu Zhao Hailing Ye Delong Lu Fengxiang Mo Xuanxue

中国地质大学 北京 100083

China University of Geosciences, Beijing, 100083

中国东部大陆裂谷系的玄武质火山活动,主要集中在三条北东向狭长的裂谷带内,由西北往东南依次为大兴安岭-太行山火山裂谷带,长白山-郯庐断裂火山裂谷带,东南沿海火山裂谷带。每个带内,第四纪玄武质火山岩沿裂谷带的轴部分布,第三纪玄武岩则分布在翼部,这和玄武岩分布在大洋中脊及翼部的规律相同:由于大陆裂谷的扩张,早期的第三纪玄武质火山由裂谷轴部向外侧迁移。中国东部大陆岩石圈是由西北往东南漂移的。中国东部大陆裂谷系的形成和扩张,与印度板块向北运动、太平洋板块向北运动有关。

Cenozoic basaltic volcanism of the eastern China continental rift system is mainly concentrated in three NE-extending narrow rift belts. From northwest to southeast, they are the Daxinganling-Taihangshan Belt, the Changbaishan-Tanlu Fault Belt and the Southeast Coast belt. In each of these belts, Quaternary basaltic volcanoes are located a-long the axial area of rift belts, whereas Tertiary basalts are distributed on each of the flanks of these belts. Similar to the distribution of basalts on mid-ocean ridge and its flanks, the earlier Tertiary basaltic volcanoes shifted outward from the axes of the rifts as a result of continental rift spreading. In addition, the axis of the Quaternary basaltic volcanoes is located in the northwest side of the Tertiary basaltic volcanoes, suggesting the continental lithosphere of the eastern China drifted southeastwards. The spreading and drifting rate of the continental rifts can be estimated respectively from the shifting distances and time interval of volcanoes. The direction of tectonic stress, which is deduced from the echelon arrangement of three NE-extending volcanic belts, suggests that the formation and spreading of the eastern China continental rift system is genetically related both to the northward movement of the India Plate and the northwestward movement of the Pacific Ocean Plate.

国家自然科学基金

https://doi.org/10.11781/sysydz199301001