摘要
通过对磁场分析发现 ,冲绳海槽中段存在线性磁异常 ,说明海槽轴部地壳已经发生破裂 ,新鲜洋壳已经生成 ,目前已进入扩张阶段 .通过对磁条带和地震地层的研究得出如下结论 :冲绳海槽的张裂具有Ⅲ幕模式 ,即中到晚中新世的开裂幕 (Ⅰ幕 )、上新世—早更新世的拉张幕 (Ⅱ幕 )以及近代的扩张幕 (Ⅲ幕 ) .冲绳海槽中段的地磁场特征和已发生扩张的红海中段的磁场非常相似 ,说明冲绳海槽可能正向着“红海阶段”
Linear magnetic anomalies have been found in the middle Okinawa Trough, it means that the continental crust has broken in the extension axis, oceanic crust has been formed. There is a three extension phases model in the Okinawa Trough, namely, “doming” from middle Miocene to early Pliocene (PhaseⅠ),“extension” from Pliocene to early Pleistocene (Phase Ⅱ), and recent “spreading” (Phase Ⅲ). The magnetic anomalies for the middle Okinawa Trough are very similar to those found in the Red Sea, which shows that developing of the Okinawa Trough is going to “Red Sea stage”. Being similar to the Red Sea, there are a “main trough” and a “axial trough” in the Okinawa Trough.
出处
《海洋学报》
CAS
CSCD
北大核心
2001年第2期69-78,共10页
关键词
冲绳海槽
磁异常
张裂带
构造发育
岩浆活动
Okinawa Trough
magnetic anomaly
tectonic development
extension phase
