海洋低信噪比单道地震资料特点及处理策略
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摘要
海洋单道地震是海洋地球物理调查的常用手段之一,具有广阔的应用前景。但单道地震单一的覆盖次数及非等间距采集模式导致剖面信噪比低、多次波发育、垂向振幅能量差异大等特点。从单道地震的采集原理出发,阐述了单道地震资料处理中的3个难点:海底同相轴抖动、强振幅海底多次、严重背景随机噪音。针对涌浪引起的海底同相轴抖动问题,借用陆地资料静校正原理,将海底抖动分为高频和低频两个分量;采用互相关技术逐步消除高低频静校正分量。针对单道资料强振幅海底多次波,根据一维SRME算法原理,对单道数据运用一维SRME算法公式,预测的多次波模型与实际的多次波模型较为接近;针对单道资料低信噪比问题,将RNA去噪技术与LIFT去噪思想相结合,达到增强有效信号的同时压制空间随机干扰的目的。实际资料处理后的剖面信噪比与分辨率均显著提升,波组特征更加突出,成果资料满足用户解释需求。
Single-channel seismics,as a common method,is widely applied in marine geophysical survey.However,the method has some disadvantages,such as low signal-noise ratio,interference of multiple wave and large difference in vertical amplitude caused by single coverage and unequal acquisition intervals.Based on the acquisition principle of single-channel seismic survey,this paper is devoted to the three difficulties in processing single channel seismic data,i.e.seafloor in-phase axis jitter,seafloor multiple waves with strong amplitude,and serious background random noise.In order to solve the problem of seafloor in-phase axis jitter caused by surge wave,we subdivided the seafloor jitters into high frequency and low frequency components according to the principles we usually used for land data static correction.Cross-correlation technique is used to gradually eliminate the high and low frequency static correction components.For multiples,one-dimensional SRME algorithm formula is applied to single-channel data processing and make the predicted multiple wave model close to the actual.Concerning the problem of low SNR of single channel data,RNA technology combined with LIFT theory is adopted to enhance signals and suppress spatial random interferences.The SNR and resolution of the actual data after processing are significantly improved,and the wave group features become clearer.
Single-channel seismics,as a common method,is widely applied in marine geophysical survey.However,the method has some disadvantages,such as low signal-noise ratio,interference of multiple wave and large difference in vertical amplitude caused by single coverage and unequal acquisition intervals.Based on the acquisition principle of single-channel seismic survey,this paper is devoted to the three difficulties in processing single channel seismic data,i.e.seafloor in-phase axis jitter,seafloor multiple waves with strong amplitude,and serious background random noise.In order to solve the problem of seafloor in-phase axis jitter caused by surge wave,we subdivided the seafloor jitters into high frequency and low frequency components according to the principles we usually used for land data static correction.Cross-correlation technique is used to gradually eliminate the high and low frequency static correction components.For multiples,one-dimensional SRME algorithm formula is applied to single-channel data processing and make the predicted multiple wave model close to the actual.Concerning the problem of low SNR of single channel data,RNA technology combined with LIFT theory is adopted to enhance signals and suppress spatial random interferences.The SNR and resolution of the actual data after processing are significantly improved,and the wave group features become clearer.
引文
[1]何汉漪.海上高分辨率地震技术及其应用[M].北京:地质出版社,2001.
[2] Weber N,Chaumillon E,Tesson M,et al.Architecture and morphology of the outer segment of a mixed tide and wave-dominated-incised valley,revealed by HR seismic reflection profiling:the paleo-Charente River,France[J].Marine Geology,2004,207(1):17-38.
[3]万芃,温明明,吴衡,等.高分辨率单道地震技术在深海探测中的应用研究[J].地质装备,2014,15(4):33-41.
[4] LeBlanc C,Louden K,Mosher D.Gas hydrates off Eastern Canada:velocity models from wide-angle seismic profiles on the Scotian Slope[J].Marine and Petroleum Geology,2007,24(5):321-335.
[5]刘玉萍,李丽青,薛花,等.短时单频脉冲震源的海洋浅地层剖面资料移频处理[J].CT理论与应用研究,2014,23(3):227-235.
[6]薛花,杜民,文鹏飞,等.非线性调频信号的浅地层剖面处理技术[J].地球物理学进展,2014,29(5):2287-2292.
[7]杨力,文鹏飞,张如伟,等.面向不同解释目的的参量阵浅剖处理[J].海洋地质前沿,2016,32(12):54-58.
[8] Manik T,Barry Z.Some recent developments in the acquisition and processing of the seismic data[J].Tectonophysics,1998,286:123-142.
[9]万芃,牟泽霖,冯强强.海洋单道地震勘探震源技术[J].中国科技信息,2015,8:65-67.
[10]褚宏宪,杨源,张晓波,等.高分辨率单道地震调查数据采集技术方法[J].海洋地质前沿,2012,28(12):70-74.
[11]丁维凤,冯霞,傅晓明,等.海上单道地震与浅地层剖面数据海浪改正处理研究[J].海洋学报,2012,34(4):91-98.
[12]李丽青,徐华宁,舒虎,等.涌浪静校正技术在海洋单道地震资料处理中的应用[J].物探与化探,2007,31(4):339-343.
[13]王惠东,潘军,颜中辉,等.东海陆架多次波特点及去除策略[J].海洋地质前沿,2017,33(4):64-70.
[14]刘伍,司永峰,王治华,等.上海近岸浅海单道地震多次波特征及压制方法研究[J].上海国土资源,2016,37(2):89-95.
[15]万芃,温明明,牟泽霖.单道地震电缆检波器线性组合特性分析[J].华南地震,2015,35(2):60-66.
[16]卢胜周,李振,马秀敏,等.单道地震勘探应用中的干扰因素分析及压制[J].四川地质学报,2016,36(2):310-315.
[17]郑江龙,许江,李海东,等.海上单道地震勘探中船舶等背景噪声的影响分析及压制[J].应用海洋学学报,2015,34(1):17-23.
[18] Verschuur D J.地震多次波去除技术的过去、现在和未来[M].北京:石油工业出版社,2010.
[2] Weber N,Chaumillon E,Tesson M,et al.Architecture and morphology of the outer segment of a mixed tide and wave-dominated-incised valley,revealed by HR seismic reflection profiling:the paleo-Charente River,France[J].Marine Geology,2004,207(1):17-38.
[3]万芃,温明明,吴衡,等.高分辨率单道地震技术在深海探测中的应用研究[J].地质装备,2014,15(4):33-41.
[4] LeBlanc C,Louden K,Mosher D.Gas hydrates off Eastern Canada:velocity models from wide-angle seismic profiles on the Scotian Slope[J].Marine and Petroleum Geology,2007,24(5):321-335.
[5]刘玉萍,李丽青,薛花,等.短时单频脉冲震源的海洋浅地层剖面资料移频处理[J].CT理论与应用研究,2014,23(3):227-235.
[6]薛花,杜民,文鹏飞,等.非线性调频信号的浅地层剖面处理技术[J].地球物理学进展,2014,29(5):2287-2292.
[7]杨力,文鹏飞,张如伟,等.面向不同解释目的的参量阵浅剖处理[J].海洋地质前沿,2016,32(12):54-58.
[8] Manik T,Barry Z.Some recent developments in the acquisition and processing of the seismic data[J].Tectonophysics,1998,286:123-142.
[9]万芃,牟泽霖,冯强强.海洋单道地震勘探震源技术[J].中国科技信息,2015,8:65-67.
[10]褚宏宪,杨源,张晓波,等.高分辨率单道地震调查数据采集技术方法[J].海洋地质前沿,2012,28(12):70-74.
[11]丁维凤,冯霞,傅晓明,等.海上单道地震与浅地层剖面数据海浪改正处理研究[J].海洋学报,2012,34(4):91-98.
[12]李丽青,徐华宁,舒虎,等.涌浪静校正技术在海洋单道地震资料处理中的应用[J].物探与化探,2007,31(4):339-343.
[13]王惠东,潘军,颜中辉,等.东海陆架多次波特点及去除策略[J].海洋地质前沿,2017,33(4):64-70.
[14]刘伍,司永峰,王治华,等.上海近岸浅海单道地震多次波特征及压制方法研究[J].上海国土资源,2016,37(2):89-95.
[15]万芃,温明明,牟泽霖.单道地震电缆检波器线性组合特性分析[J].华南地震,2015,35(2):60-66.
[16]卢胜周,李振,马秀敏,等.单道地震勘探应用中的干扰因素分析及压制[J].四川地质学报,2016,36(2):310-315.
[17]郑江龙,许江,李海东,等.海上单道地震勘探中船舶等背景噪声的影响分析及压制[J].应用海洋学学报,2015,34(1):17-23.
[18] Verschuur D J.地震多次波去除技术的过去、现在和未来[M].北京:石油工业出版社,2010.
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