海底多分量中的直达波、鬼波及水柱混响

Direct arrival , ghost wave and water column reverberation on sea-bottom multi-component data.

本文根据两层简单海洋模型 ,在忽略不计海底摩擦阻力的条件下 ,求解水中震源所形成的海洋地震波场 ,给出海底多分量的接收特性 ,进而用傅里叶方法得到水中震源的海底多分量理论记录。算例表明 :海底压强分量及垂直分量中有直达波、鬼波以及各自的水柱混响等声波干扰 ,这两种分量上的声波干扰反相 ,便于压制。在海底阻力较小或趋于零的条件下 ,海底径向水平分量中没有上述声波干扰 ,在海底摩擦阻力大的条件下 ,可能存在这类干扰。

Based on a simple two layered marine model,the paper seeks a solution of marine seismic wavefield formed by the source in water when frictional drag of sea bottom can be neglected,gives a receiving character on sea bottom multi component receiver and obtains theoretic sea bottom multi component records from source in water by Fourier method. The test example shows that there is sonic interference such as direct arrival, ghost wave and respective water column reverberation in sea bottom pressure component and vertical component and the sonic interference has opposite phase in these two components so that can be easily compressed. There is not above mentioned sonic interference in radial horizontal sea bottom component if frictional drag of sea bottom is feeble or tends to zero,otherwise (strang frictional drag of sea bottom), these interference may exist.