单点数字检波器地震资料特点及处理对策

Seismic data character of single-point digital geophone and processing strategy.

数字检波器单点采集的地震资料具有高分辨率、低信噪比等特点,针对分辨率、信噪比这一对矛盾,基于数字检波器的基本原理,本文提出了在多域、多次应用多种提高分辨率与信噪比方法进行迭代处理,既能提高资料的分辨率,又能提高信噪比,做到了高分辨率与高信噪比的最佳结合,得到以下认识:①数字检波器资料由于频带宽、频率动态范围变化大,在提高分辨率的同时频带进一步拓宽,会伴生许多高、低频噪声,使信噪比明显降低,因此需要在提高分辨率的同时利用多种去噪手段压制噪声;②利用炮域地表一致性反褶积、CMP域统计子波反褶积、优选炮检距叠加+叠后预测反褶积+反Q滤波等方法,可有效地提高资料的分辨率,但同时也在一定程度上降低了信噪比;③利用在炮域压制面波与异常噪声,在CMP域压制高频噪声,叠后压制随机噪声与高频噪声,小面元资料的道组合技术组合叠加等去噪技术,可有效地提高资料的信噪比。利用文中方法完成了垦71地区数字检波器三分量资料处理工作,最终处理结果的同相轴形态清晰、相干性好、对比性好、可解释性强,信噪比和分辨率都得到了提高。

The seismic data acquired by single-point digital geophone is characterized by high resolution and low S/N ratio. Due to a pair of contrary of resolution and S/N ratio and based on basic principle of digital geophone, the paper presented using multiple application of multiple methods improving resolution and S/N ratio in multi-domain to carry out iterative processing, which improves both resolution and S/N ratio of data, successfully realizing optimum combination of improving resolution with improving S/N ratio and getting following knowledge: ①since broad band and large dynamic range of frequency of digital geophone data, resolution improving while further broadening band may associate with a lot of noises with higher and lower frequencies, lowering S/N ratio significantly, it should use multiple denoise tools to suppress noise while improving resolution; ②using surface-consistent deconvolution in shot domain, statistic wavelet deconvolution in CMP domain, optimized offset stack plus poststack predictive deconvolution plus inverse Q-filtering can effectively improve the resolution of data, and lowering the S/N ratio in a certain degree at the same time; ③using following techniques such as suppressing plane and anomalous noises in shot domain, suppressing high-frequency noises in CMP domain, poststack suppressing random noise and high-frequency noises and channel array technique and array stack for small bin-size data can effectively improve S/N ratio of data. Using the methods presented in the paper finished the 3D data processing of digital geophone in the Keng-71 area, the events in final processed results are characterized by clear configuration, good coherence, good correlation, better interpretable property and improvement in both S/N ratio and resolution.