论文详情
转换波地震勘探是海上和陆上多波多分量地震勘探的主要工作方法。由于转换波具有传播速度低、吸收衰减大、能量相对较弱等特点,因此其地震资料静校正问题突出。常规转换波静校正方法在表层纵横波速度比不详、横波初至不易识别的情况下,效果都不太理想。针对转换波静校正难点,提出了多波联合的转换波折射静校正技术,该技术通过P-P-P折射波初至拾取技术和P-P-SV折射波共检波点初至叠加技术的联合,实现了P-P-SV折射波初至的成像及准确识别；以此为基础,再联合利用P-P-P折射波折射静校正技术和P-P-SV折射波延迟时差提取技术,求取P-P-SV折射波检波点延迟时间。最后,根据P-P-SV折射波检波点延迟时间,求解出P-SV波检波点基准面静校正量。实际数据测试结果表明,多波联合的转换波折射静校正技术提高了转换波检波点静校正量计算精度,能够明显提高转换波资料成像质量。
The converted wave seismic exploration is the main method of multi-wave and multi-component seismic exploration applied to onshore and offshore exploration.However,the converted wave is characterized by low velocity,serious absorption and attenuation,weak energy and so on,which highlights static correction of converted wave.Research of converted wave static correction undertaken by many researchers is of little help,when surface P-velocity/S-velocity is unknown and first break of S-wave is difficult to identify.We propose a refraction static correction technique for multi-wave combined converted wave aimed at the difficulty.This technique achieved P-P-SV first break imaging and identification by the combination of the first break pickup for P-P-P refraction wave and the first break stacking in CRP gather for P-P-SV refraction wave.On this basis,to solve the delay time of receiver point for P-P-SV refraction wave we combined the refraction static correction of P-P-P refraction wave with the delay time extraction of P-P-SV refraction wave.At last,according to the delay times of receiver point for P-P-SV refraction wave,the datum level statics of P-SV receiver point can be obtained.The experimental result shows that the refraction static correction technique of multi-wave combined converted wave improved the calculation accuracy of converted wave static correction and the imaging quality.
国家自然科学基金项目(41204101)和四川省重点实验室开放基金项目(2015trqdz03)联合资助。