摘要
在油田近地表勘探中,可以利用现有的地震大炮记录中的瑞利波信息进行频散成像,提取瑞利波频散曲线反演近地表的横波速度结构。由于大炮地震记录的采集排列很长,且不同炮检距范围内瑞利波数据的频散成像结果存在差异,从而会对频散曲线的提取和反演结果产生影响。笔者利用胜利油田LJ地区的盒子波地震数据,从频散成像的分辨率和连续性两个方面,分析了不同排列长度和不同偏移距下的频散成像结果,发现长排列可以有效提高频散成像的分辨率,且在较近偏移距下的频散成像效果更好。同时,验证了Zhang2004年提出的最优偏移距计算公式在石油近地表勘探中的有效性及适用性,并可以作为近地表瑞利波勘探时最优偏移距的选择标准。
The surface velocity structure can be estimated by inverting the dispersion curve extracted from the dispersion image result of the Rayleigh-wave information in shot gathers of near-surface exploration. The dispersion image results from the difference of Rayleighwave data in different offset ranges,and will affect the extraction and inversion results of the dispersion curve. In this paper,the authors studied the dispersion imaging results in different collection arrangements and offsets by dispersion imaging resolution and continuity using box wave in LJ area of the Shengli oilfield,and found that the long collection arrangement can improve the dispersion imaging resolution effectively,and that the dispersion imaging result in near offset is better. The authors also tested and verified the effectiveness and applicability of the optimum offset formula proposed by Zhang in 2004,and the results show that it can be used as a standard of the optimum offset in near-surface Rayleigh-wave exploration.
出处
《物探与化探》
CAS
CSCD
2013年第6期1085-1091,共7页
Geophysical and Geochemical Exploration
关键词
近地表勘探
频散成像
分辨率
最优偏移距
near-surface exploration
dispersion image
resolution
optimum offset
