【摘要】 在处理海上地震资料时,发现浅层海底的成像在叠加剖面和叠后时间偏移剖面上很清楚,但在叠前时间偏移剖面上却不清楚。应用叠前时间偏移成像的理论公式对此现象进行分析,并结合浅层海底模型进行了偏移试验,最后用实际资料验证了解决方案的可行性。研究表明,浅层海底是否能够成像,取决于叠前时间偏移中输出线成像位置的确定:只有将输出线放在近炮成像点上或者附近,才能看到海底的成像;在远炮成像点处,海底不能成像。更多还原

【Abstract】 It is found that shallow seafloors cannot be clearly imaged on pre-stack time migration sections while they could be clearly seen on stacked and post-stack time migration sections.The equations of pre-stack time migration are used to analyze the problem.We conduct a migration test of shallow water model and a migration of field data to verify our idea,and achieve very satisfactory results.It has been shown that the shallow seafloor imaging depends on the positions of output imaging lines in pre-stack time migration.The events on shallow seafloor are clearly imaged only when the output lines are on or near the near-shot imaging points;they cannot be correctly imaged when the output lines are far away from the near-shot imaging points.更多还原