Abstract：The low resolution of seismic data is a prominent problem in the current deep seismic exploration in Bohai Sea. In order to solve this problem,it is necessary to find breakthroughs in seismic acquisition,especially in the source design. However,there are few reports on the research of spatial combination of the streamer and source in shallow water conditions of Bohai Sea. This paper firstly analyzes the characteristics of air gun pulse propagation in shallow water conditions of Bohai Sea and determines the main factors affecting the air gun pulse propagation. Then,the paper simulates the single gun wavelet in shallow water based on the non-ideal gas condition air gun wavelet model,studied the spectral characteristics of the wavelet by considering the streamer ghost, and proposes the method of evaluating the source performance with the wavelet including streamer ghost. Secondly,based on the actual geographical and geological conditions in Bozhong area of Bohai Sea,the paper designs the simulation tests of different cable-source sinking depth combinations and source plane distribution and analyzes systematically the influence law of spatial combination of the streamer and source on wavelet and its frequency spectrum under the condition of shallow water in Bohai Sea. Finally,the paper applies the summarized law understanding and source design technology to the secondary data acquisition of Bozhong and compares the new and old three-dimensional towing cable single shot in Bozhong area,which verifies the correctness of the proposed method. The research results have a certain guiding significance for the optimal design and evaluation of air gun sources in the shallow water area of Bohai Sea.
XIA Ji,JIN Xing,CAI Huiteng,et al. The time-frequency characteristic of large capacity air-gun array wave and its influencing factors[J]. Journal of Seismological Research, 2017,40(1):111-121.夏季,金星,蔡辉腾,等. 大容量气枪阵列子波时频特性及其影响因素[J]. 地震研究,2017,40(1):111-121.
[2]
CHEN Haolin,QUAN Haiyan,YU Guoping,et al. Summary of airgun source theory and technology(1)[J]. Equipment for Geophysical Prospecting,2008,18(4):211-217.陈浩林,全海燕,於国平,等. 气枪震源理论与技术综述(上)[J]. 物探装备,2008,18(4):211-217.
[3]
ZIOLKOWSKI A. A method for calculating the output pressure waveform from an air gun[J]. Geophysical Journal of the Royal Astronomical Society,1970,21(2):137-161.
[4]
SAFAR M H. The radiation of acoustic waves from an air-gun[J]. Geophysical Prospecting,1976,24(4):756-772.
[5]
GILES B F. Pneumatic acoustic energy source[J]. Geophysical Prospecting,1968,16(1):21-53.
[6]
PARKES G E,HATTON L,HAUGLAND T. Marine source array directivity:a new wide airgun array system[J]. First Break,1984,2(7),DOI:10.3997/1365-2397.1984013.
[7]
NOOTEBOOM J J. Signature and amplitude of linear airgun arrays[J]. Geophysical Prospecting,1978,26(1):194-201.
[8]
DI Bangrang,TANG Bowen,CHEN Haolin,et al.Study on theoretical waveform from air guns[J]. Journal of the University of Petroleum,China (Edition of Natural Science),2003, 27(5):32-35.狄帮让,唐博文,陈浩林,等. 气枪震源的理论子波研究[J]. 石油大学学报(自然科学版),2003,27(5):32-35.
ZHANG Peng,YANG Kai,LI Xin,et al. The optimal design of point source air-gun array in marine and its application[J]. Oil Geophysical Prospecting,2015,50(4):588-599.张鹏,杨凯,李欣,等. 海上空气枪点震源阵列的优化设计及应用[J]. 石油地球物理勘探,2015, 50(4):588-599.
[11]
CAO Mingqiang,NI Chengzhou,NIU Hongxuan,et al. Signature directivity of air gun array in marine seismic exploration[J].Oil Geophysical Prospecting,2014,49(2):236-238.曹明强,倪成洲,牛宏轩,等. 海上地震勘探气枪阵列子波方向性分析[J]. 石油地球物理勘探,2014,49(2):236-238.
[12]
SUN Yuyao. The discussion of the influence of air gun depth on wavelet[J]. Inner Mongolia Petrochemical Industry,2016,42(5):52-54.孙郁遥. 探讨气枪沉放深度对子波的影响[J]. 内蒙古石油化工,2016,42(5):52-54.
[13]
LI Xuxuan,WANG Jianhua,YANG Kai,et al. A study on optimization of seismic air-gun array source and its application in offshore deep water[J]. China Offshore Oil and Gas,2012,24 (3):1-6,16.李绪宣,王建花,杨凯,等. 海上深水区气枪震源阵列优化组合研究与应用[J]. 中国海上油气,2012,24(3):1-6,16.
[14]
LI Xuxuan,WEN Shuliang,GU Hanming,et al. A numerical simulation of wavelets from offshore air-gun array seismic source[J]. China Offshore Oil and Gas,2009,21(4):215-220.李绪宣,温书亮,顾汉明,等. 海上气枪阵列震源子波数值模拟研究[J]. 中国海上油气,2009,21(4):215-220.
[15]
WANG Jianhua,LI Xuxuan,GU Hanming. The optimal design of 3D air-gun arrays combination in marine seismic exploration[J]. Geological Science and Technology Information,2012,31(2):133-138.王建花,李绪宣 顾汉明. 海上多子阵立体组合气枪震源优化设计[J]. 地质科技情报,2012,31(2):133-138.
[16]
WANG L M,Hu Y,WANG Y,et al. Source wavelet simulation of GI gun[J]. Progress in Geophysics,2015,30(6):2793-2796.王立明,胡毅,王瑜,等. GI枪结构震源子波模拟研究[J]. 地球物理学进展,2015,30(6):2793-2796.
[17]
LIN Jianmin,WANG Baoshan,GE Hongkui,et al. Characters of large volume air-gun source excitation[J]. Chinese Journal of Geophysics,2010,53(2):342-349.林建民,王宝善,葛洪魁,等. 大容量气枪震源子波激发特性分析[J]. 地球物理学报,2010,53(2):342-349.
WANG Fengfan. Research on Simulation and Design of Signature Produces by Marine Multi-level Air-gun Array[D]. Ocean University of China,Qingdao,Shandong,2015.王风帆. 海上立体气枪阵列信号模拟与设计方法研究[D]. 山东青岛:中国海洋大学,2015.
[20]
ZHANG Wei. Research on the Deghosting Method in the Background of Undulating Sea Surface[D]. Jilin University,Changchun,Jilin,2017.张威. 起伏海面背景下的鬼波压制方法研究[D]. 吉林长春:吉林大学,2017.
[21]
LI Haijun,GAO Bin,SHI Ying,et al. Research on low-frequency expansion methods for air-gun source[J]. Equipment for Geophysical Prospecting,2020,30(5):306-310.李海军,高斌,史颖,等. 气枪震源低频拓展方法研究[J]. 物探装备,2020,30(5):306-310.
