摘要
介绍了一种在无井或少井情况下的叠前叠后混合地震反演方法。该方法充分利用了叠前反演分辨率高和叠后反演效率高、抗噪能力强的优点。首先应用遗传算法理论在所选控制点的角道集数据上进行叠前波形反演,求取控制点的虚拟纵波速度曲线;然后利用纵波速度曲线和已知地质信息来建立初始模型,进行叠后约束反演。我国东海南部陆架盆地勘探程度低、探井数量少,适合于混合地震反演技术的应用。利用该地区的实际资料进行了混合地震反演,并对影响混合地震反演效果的关键因素(层速度、角道集数据、迭代次数、已知地质信息)进行了分析。结果表明,为了获取虚拟纵波速度,需要准确的速度谱和角道集数据;为了增强叠前反演的实用性,需要选择恰当的控制点;充分利用已知地质信息,可以减小叠后反演结果的多解性。
A combination of prestack and poststack hybrid seismic inversion in exploring areas with sparse or no well control was presented. The hybrid inversion takes advantages of the high resolution of prestack inversion results and the high efficiency and stronge antinoise capability of poststack inversion results. In the methodology, a genetic algorithm （GA） was used at selected control locations over the angle gather data volume in prestack waveform inversion, and the pseudo P-wave velocities at these locations were given. An initial model for poststack constrained inversion was built based on these pseudo P-wave velocities and known geological information. The southern shelf basin of east China Sea is an exploring new area with sparse well controlled, and the hybrid seismic inversion was applied. The key influential factors including interval velocity, angle gather data, iterations, known geological information on the hybrid seismic inversion were analyzed. The results show that to achieve pseudo P-wave velocities, accurate interval velocity and angle gather data are necessary. And in order to enhance the practicability of prestack inversions, it is necessary to select the control locations. The ambiguity of the poststack inversion can be reduced by putting the known geological information to good use.
出处
《中国石油大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2007年第5期28-34,40,共8页
Journal of China University of Petroleum(Edition of Natural Science)
基金
国家'863'计划项目(2003AA611010-03)
