【摘要】 位于东海陆架与琉球岛弧之间的冲绳海槽为板块俯冲作用形成的弧后断陷盆地,具有独特的构造地貌特征。自中新世末以来历经了4个强烈拉张的演化时期,目前已达到张裂的高级阶段。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地堑槽,对称分布的张性断裂,晚更新世—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,充分体现了冲绳海槽的现代扩张特点。更多还原

【Abstract】 Okinawa Trough,a back-arc fault basin that was formed by the plate collision and subduction,is located between the continental shelf of the East China Sea and Ryukyu Island arc.It has unique tectonic geomorphological features.The back-arc faulting started in Miocene,and the tension of fracture is continuing now.Okinawa Trough has undergone four intensive stages of tension evolution since the end of Miocene and now it is in the high stage of tension.According to geophysical data,modern tension action is still active in the Trough.For examples,the graben trough was caused by rapid subsidence of the axis of the Okinawa Trough and tension faults were formed symmetrically,and aslo there were magmatic activities,frequent earthquakes and high heat-flow phenomena from late Pleistocene to Holocene In addition,there are the zones of magnetic anomalies ranging from old to new ones.The tension characteristics of the Okinawa Trough in modern times have sufficiently been proved.更多还原