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1992年6月对冲绳海槽进行了热水活动和底质调查。从所采岩芯中挑选有代表性的岩芯6个，对样品进行了放射性同位素Th、230Th、232Th、U、234U、238U的测定。结果表明，冲绳海槽全新世期间沉积物沉积速率比晚更新世期间低，全新世平均沉积速率为2．10—8．50cm／ka，晚更新世平均沉积速度为7．40－20．10cm／ka。这揭示了晚更新世低海平面期间大量的陆源物质和火山碎屑输入到冲绳海槽，而全新世海平面抬升，输入到海槽的陆源物质相对减少。
In June 1992, Okinawa Trough carried out hot water activities and sediment survey. Six core samples were selected from the collected cores and the samples were tested for Th, 230Th, 232Th, U, 234U and 238U radioactive isotopes. The results show that sediments of the Okinawa Trough during the Holocene sedimentation rate lower than during the late Pleistocene, Holocene average deposition rate of 2.10-8.50cm / ka, Late Pleistocene average deposition rate of 7.40-20.10cm / Ka. This revealed a large amount of terrigenous and volcanic debris input into the Okinawa Trough during the low Pleistocene sea level, while the sea level rise of the Holocene reduced the amount of terrigenous material input to the trough.