声学地层剖面深水探测研究与开发

Technology research and development for acoustic subbottom survey in deep sea

深水浅部地层精细探测是深海地质勘探与资源开发的重要调查内容。与浅水海域声学地层剖面探测相比,深水地层剖面探测会遇到严重的能量衰减、大数据量长时间反射序列采样、纵向地层分辨率降低以及横向空间覆盖率偏稀等问题,为解决这些问题,国外仪器商采用了不同的方法。采取重采样减少数据量会严重影响纵向分辨率;采取MultiPing技术可以很好解决横向空间覆盖率问题,但多Ping接收采用海底追踪变深度范围采集会造成反射同相轴跳跃突变,或采用短时间间隔采集会造成回波数据无法准确计算海底深度。为了解决这些技术问题,作者研究开发了相关的技术处理方法,解决MultiPing技术反射同相轴拼接改正处理和海底深度记录延迟处理,这些问题的解决为深水浅部地层精细探测提供了技术保障。

Detailed survey of acoustic subbottom is important for deep ocean geological exploration and resource ex-ploitation.Compared to survey in shallow ocean water,deep sea survey faced some serious problems such as energy strongly attenuation,long reflection time series and large digital data size,the vertical stratigraphic resolution reduc-tion,and low transverse space coverage.In order to resolving these problems,main instrument manufactures in the world adopted different possible methods.For example,resampling long reflection time series can decrease the data size,but it strongly reduce vertical stratigraphic resolution.Taking MultiPing technology can solve the transverse space coverage well,but its variable depth range acquisition by seafloor reflection tracking will cause serious jump-ing off in reflection events,or it cannot get the correct seafloor reflection depth by acquisition with MultiPing trans-mitting interval.This study further independently developed some related technologies,and correctly solved the re-flection events＇jumping off,and got the recording time delay in computing the deep seafloor depth.All these tech-nologies obtained in the present study will provide some technical support for future acoustic subbottom detailed survey in deep sea.