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根据1990年以来对冲绳海槽地质地球物理调查的最新实测资料，包括多道和单道反射地震、海底地震仪折射地震、重磁测量、水深测量、海底岩石拖网，结合国内外学者对冲绳海槽的调查研究成果，对冲绳海槽地壳结构进行了探讨，得出如下初步结论：（1）冲绳海槽是一个典型的发育在大陆地壳边缘、由陆壳张裂而成、处于裂谷作用最高演化阶段、洋壳即将产生、海底扩张即将出现的弧后活动裂谷。（2）根据火成岩发育、沉积层分布和地壳结构分析，冲绳海槽尚缺少已经开始“扩张”的证据，还不能确定海槽中央已经发育了大洋地壳。冲绳海槽目前仍属于拉薄的大陆地壳。（3）冲绳海槽作为一个浅海槽状地貌单元，形成于距今6Ma。作为一个弧后裂谷，自距今2Ma以来开始强烈的张裂活动。海槽中央张裂地堑（槽中槽）距今2Ma以来开始形成并逐渐发展。中央张裂地堑内的火成岩年龄不大于1Ma。因此，冲绳海槽是一个年青的、正在活动的弧后裂谷盆地。
Based on the latest measured data of the geophysical and geophysical survey of the Okinawa Trough since 1990, including multi-channel and single-channel reflection earthquakes, seismographic seismic refraction, gravity and magnetic measurements, water depth measurement and seabed rock trawling, The results of the investigation and research of the trough, discussed the crustal structure of the Okinawa Trough, reached the following preliminary conclusions: (1) The Okinawa Trough is a typical development in the continental crust edge, formed by the cracking of continental crust, in the role of rift At its highest stage of evolution, the oceanic crust is about to emerge, and the impending rift behind the arc of seafloor expansion appears. (2) According to the distribution of igneous rocks and the analysis of crustal structure, the Okinawa Trough lacked the evidence that “expansion” has started. It is not certain that the oceanic crust has developed in the central trough. The Okinawa Trough is still a thinly populated continental crust. (3) Okinawa Trough as a shallow sea trough-like topography unit, formed in 6Ma. As a post-arc rift, since the 2Ma since the beginning of a strong crack activity. The trenches in the central trough of the trough (trench trough) began to form and develop gradually since 2Ma. The age of igneous rocks within the central Zhang Graben should not exceed 1Ma. Therefore, the Okinawa Trough is a young, active post-arc rift basin.