Abstract：The Kulongshan mountainous area is rich in oil and gas resources in Jiuquan Basin. It is characterized by both complex in near-surface and overthrust subsurface structures, leading to great difficulties in subsurface accurate imaging. Conventional floating-datum-based prestack migration doesn't work well in such an area, so that problems such as insufficient static correction, inadequate adjustment of floating datum to severely undulating surface, and inaccurate shallow velocity models affecting the migration accuracy of deeper structures are presented, and the conventional method cannot satisfy the requirement for precise imaging of the overthrust structures. This paper proposes an integration strategy of static correction and depth imaging. Combining with the partitioned double-variable static correction, it can improve the accuracy of high-frequency near-surface static correction. The key technique integrates near-surface refraction inverted velocity with deep reflection inverted velocity reasonably to acquire a high-precision global velocity model, and uses pre-stack depth migration of true surface with small-scale surface smoothing parameters to enhance the deep imaging accuracy. Application of the high-precision depth modeling and imaging processing technique to raw data shows that the method can improve the imaging quality and accuracy of complex thrust structure effectively, proving the superiority and feasibility of the method for high-precision modeling and imaging in complex areas.
肖明图, 苏勤, 余国祥, 李斐, 凌越, 邵喜春. “双复杂”条件高精度建模与成像方法——以酒泉盆地窟窿山地区为例[J]. 石油地球物理勘探, 2020, 55(s1): 41-48.
XIAO Mingtu, SU Qin, YU Guoxiang, LI Fei, LING Yue, SHAO Xichun. Research on high-precision modeling and imaging with dual-complexity conditions: Taking the Kulongshan mountainous area of Jiuquan Basin as an example. Oil Geophysical Prospecting, 2020, 55(s1): 41-48.
贾承造,宋岩,魏国齐,等.中国中西部前陆盆地的地质特征及油气聚集[J].地学前缘,2005,12(3):3-13.JIA Chengzao,SONG Yan,WEI Guoqi,et al.Geological features and petroleum accumulation in the foreland basins in central and western China[J].Earth Science Frontiers,2005,12(3):3-13.
[2]
潘良云,孙星,孙学栋,等.酒泉盆地窟窿山构造特征与油气成藏规律[J].石油地球物理勘探,2007,42(1):115-119.PAN Liangyun,SUN Xing,SUN Xuedong,et al.Structural feature and oil/gas accumulation rule in Kulongshan mountain of Jiuquan basin[J].Oil Geo-physical Prospecting,2007,42(1):115-119.
[3]
王卫华.速度横向变化对地震成像的影响[J].石油地球物理勘探,2007,42(6):720-726.WANG Weihua.Influence of lateral velocity variation on seismic imaging[J].Oil Geophysical Prospecting,2007,42(6):720-726.
[4]
熊翥.复杂地区地震数据处理思路[M].北京:石油工业出版社,2002.
[5]
苟量,贺振华.西部复杂山地勘探走势分析[J].石油地球物理勘探,2005,40(2):248-251.GOU Liang,HE Zhenhua.Analysis of trend to complex mountainous exploration in west of China[J].Oil Geo-physical Prospecting,2005,40(2):248-251.
[6]
赵波,钱忠平,王成祥,等.复杂山地构造综合模型建立与地震波模拟[J].石油地球物理勘探,2015,50(3):475-482.ZHAO Bo,QIAN Zhongping,WANG Chengxiang,et al.Complex mountain 2D-model building and seismic wave modeling[J].Oil Geophysical Prospecting,2015,50(3):475-482.
[7]
Berryhill J R.Wave equation datuming before stack[J].Geophysics,1984,49(11):2064-2066.
[8]
Wiggins J W.Kirchhoff integral extrapolation and migration of nonplanar data[J].Geophysics,1984,49(8):1239-1248.
[9]
Gray S H and Marfurt K J.Migration from topography:Improving the near-surface image[J].Canadian Journal of Exploration Geophysics,1995,31(1):18-24.
[10]
秦宁,王延光,杨晓东,等.非水平地表高斯束叠前深度偏移及山前带应用实例[J].石油地球物理勘探,2017,52(1):81-86.QIN Ning,WANG Yanguang,YANG Xiaodong,et al.Gaussian beam prestack depth migration for undula-ting-surface area in piedmont zone[J].Oil Geophysical Prospecting, 2017,52(1):81-86.
[11]
王华忠,刘少勇,杨勤勇,等.山前带地震勘探策略与成像处理方法[J].石油地球物理勘探,2013,48(1):151-159.WANG Huazhong,LIU Shaoyong,YANG Qinyong,et al.Seismic exploration strategy and image processing in mountain areas[J].Oil Geophysical Prospecting,2013,48(1):151-159.
[12]
杨海申,蒋先艺,高彦林,等.复杂区三维折射静校正技术与应用效果[J].石油地球物理勘探,2005,40(2):219-225.YANG Haishen,JIANG Xianyi,GAO Yanlin,et al.3D refraction static corrections in complex regions and its applied effects[J].Oil Geophysical Prospecting,2005,40(2):219-225.
臧胜涛,苏勤,王建华,等.山地复杂构造带地震资料处理方法[J].石油地球物理勘探,2018,53(增刊1):62-68.ZANG Shengtao,SU Qin,WANG Jianhua,et al.Seismic data processing methods for complex moun-tainous areas[J].Oil Geophysical Prospecting,2018,53(S1):62-68.
[16]
王伟,陈双廷,王宝彬,等.五维规则化技术研究与应用[J].石油地球物理勘探,2017,52(增刊1):28-33.WANG Wei,CHEN Shuangting,WANG Baobin,et al.Application of 5D regularization in seismic data pro-cessing[J].Oil Geophysical Prospecting,2017,52(S1):28-33.
[17]
臧殿光,张延庆,李丰,等.解释性目标处理技术在龙门山冲断带的探索应用[J].石油地球物理勘探,2016,51(增刊1):71-76.ZANG Dianguang,ZHANG Yanqing,LI Feng,et al.Interpretation-oriented processing methods for thrust belts in Longmen Mountain Area[J].Oil Geophysical Prospecting,2016,51(S1):71-76.
