摘要
叠前偏移处理技术是解决精细速度分析和复杂构造成像的有效手段之一.叠前时间偏移处理是近年来国内外地震资料常规处理的发展趋势,它可获得偏移归位后的速度场,适用于陡倾角构造和深部构造的准确成像.在渤南海区垦利11-2构造上,叠前时间偏移处理的剖面较叠后偏移处理的剖面有较大改善,构造成像质量得到提高,断面及地层不整合关系较清晰,据此得到了新的更准确的解释方案.在南黄海盆地北部凹陷应用叠前深度偏移处理技术很好地解决了逆断层的归位和下盘的准确成像.在琼东南盆地松涛36-1构造上,叠前深度偏移处理消除了由于海底崎岖造成横向速度变化所引起的下伏地层变形和不成像问题,证实了构造北倾存在,恢复了构造的真实面貌,获得了很好的地质效果,使得该构造的解释工作有了突破性的进展.采用先进的二维多测线深度域叠前偏移处理和成图技术成功地对乐东22-1构造中深层"模糊带"进行了精细速度反演,实现了深度构造图的成图,落实了乐东22-1构造中深层存在圈闭,为发现乐东22-1气田提供了准确的构造图,为勘探项目提供了坚实有力的技术支持.
Seismic prestack migration is one of the effective techniques for accurate velocity analysis and complex structure imaging. Prestack time migration has become a trend in conventional seismic processing recently, which can acquire migrated velocity field suitable to accurate imaging of the deep and dip structures. On Kenli 11 2 structure in the offshore Bonan area, the prestack time migration section is considerably improved compared with poststack time migration section, with structure imaging quality greatly enhanced and faults and unconformities much clearer, resulting in a new and more accurate interpretation. In the northern depression of South Huanghai Basin, the prestack depth migration technique has achieved location of reverse faults and accurate imaging of their footwalls. On Songtao 36 1 structure in Qiongdongnan Basin, the prestack depth migration processing has removed distorted and no imaging of formation caused by great lateral change in velocity due to rugged sea bottom. Therefore, north dipping of the structure is confirmed and its actual configuration is reconstructed, leading to a breakthrough in interpretation of the structure. For the mid deep 'gas cloud' zone of Ledong 22 1 structure, refined velocity inversion has been conducted by advanced 2D multi line prestack depth migration processing and mapping techniques, resulting in construction of depth map and confirmation of a mid deep trap for the structure. All these promoted the discovery of Ledong 22 1 gas field, and provide a strong support to the exploration project.
出处
《中国海上油气（地质）》
2001年第5期361-364,370,T005-T006,共7页
China Offshore Oil and Gas(Geology)
关键词
地震资料处理
叠前偏移处理
精细速度分析
法向速度
复杂构造成像
prestack time migration
prestack depth migration
normal direction velocity
vertical velocity
map migration
rugged sea bottom
reverse fault
2D multi line processing in depth
