冲绳海槽现代张裂特征研究

A Study on Modern Tectonic Tension Fault in the Okinawa Trough

杨文达 张异彪 施健

YANG Wen-da ZHANG Yi-biao SHI Jian

中石化集团上海海洋石油局第一海洋地质调查大队, 上海 201208; 中国海洋大学, 青岛 266003

No.1 Marine Geological Party, Shanghai Offshore Petroleum Bureau, SINOPEC, Shanghai 201208, China; China University of Marine, Qingdao 266003, China

冲绳海槽自中新世末以来历经了四个强烈拉张的演化过程,综合地球物理资料显示,海槽中的现代拉张作用仍在进行,表现在海槽轴部快速沉降形成的地堑槽,对称分布的张性断裂,晚更新世至全新世以来的岩浆活动,从老至新排列的磁异常条带以及高地热流、频繁的地震活动等,充分表明了冲绳海槽的现代扩张特点。

Okinawa Trough has undergone four vehement tension evolution since the end of Miocene and has come up high stage of tension. According to the geophysical data, modern tension action is still carrying on in the trough. This could be proved through the graben trough which has been formed as rapid subsidence of the axis of Okinawa Trough, tension fault which has been formed symmetrically, magmatic evolution from late Pleistocene to Holocene, zones of magnetic anomaly arraied from old ones to new ones, frequent seism, high heat-flow, and so on. The tension characteristics of Okinawa Trough in modern times have been sufficiently proved.